docs(adr): split ADR-0026 + propose ADR-0027 (Structure hierarchy)

Cascade + acteurs_plus source-of-truth audit caught the original
ADR-0026 draft pinning Etablissement.finess as PK while >=30% of
APF's real structure inventory has no FINESS (antennes, dispositifs,
entreprises adaptees, mouvement, administratif, siege).

Narrow ADR-0026 to identity only (Person + User + UserScope). Drop
Person.email unique (two distinct humans can share an email) and
drop email-based dedup from the v1 provisioner lifecycle - entraOid
is the only natural key trusted in v1.

New ADR-0027 owns the organisational hierarchy: cascade-aligned
Structure with kind discriminator + nullable FINESS / SIRET /
codePaie + internal code PK that doubles as FINESS for medico-social
structures. Pole / Service / arbitrary nesting / per-source
enrichment deferred to ADR-0028 (sync), renumbered from the prior
ADR-0027 placeholder.

Both ADRs stay proposed pending review.

docs/decisions/0026-person-user-portal-data-model.md

@@ -5,15 +5,14 @@ decision-makers: R&D Lead
 tags: [data, backend, security]
 ---
 
-# `Person` golden record + `User` portal-account + organisational hierarchy — portal-side data model
+# `Person` golden record + `User` portal-account — portal-side identity model
 
 ## Context and Problem Statement
 
-[ADR-0025](0025-authorization-model-privileges-roles-scopes.md) shipped the authorization model — three orthogonal axes (privileges × functional roles × scopes) — but left several anchors as proposed-follow-up. In v1 those anchors are stubbed:
+[ADR-0025](0025-authorization-model-privileges-roles-scopes.md) shipped the authorization model — three orthogonal axes (privileges × functional roles × scopes) — but left two identity anchors as proposed-follow-up. In v1 those anchors are stubbed:
 
 - `Principal.user.id` and `Principal.user.personId` are populated with the Entra `oid` as a placeholder, because no portal-side identity record exists yet (see [ADR-0025 §"Principal shape"](0025-authorization-model-privileges-roles-scopes.md) and the BFF builder at `apps/portal-bff/src/auth/principal-builder.ts`).
 - `ScopeResolver` returns `[{ kind: 'unrestricted' }]` for every signed-in user (see `StubScopeResolver` and [ADR-0025 §"Sources of truth — apf_portal-side `user_scopes` table"](0025-authorization-model-privileges-roles-scopes.md)). The intended per-persona scopes documented in `notes/test-tenant-role-assignments.md` have nowhere to live.
-- `@RequireScope`'s `ScopableResource` shape — `etablissementFiness`, `delegationCode`, `regionCode`, `isSiege` — describes a parentage chain the BFF cannot actually fetch because there is no `Etablissement` / `Delegation` / `Region` table.
 
 The portal also needs a representation of **people who are not yet portal users**. APF France handicap touches three populations with very different relationships to the portal:
 
@@ -21,22 +20,22 @@ The portal also needs a representation of **people who are not yet portal users*
 2. **Governance** (élus du CA national + élus des CD départementaux) — many will be portal users; their identity, mandate type, and mandate scope come from Acteurs+ (the governance system).
 3. **Bénévoles + adhérents + bénéficiaires** — most will not be portal users; their identity lands in the portal via the membership / dossier flows.
 
-A naive "User table = anyone who ever signed in" model collapses these three populations into one bucket and loses two important capabilities the portal needs from day one:
+A naive "User table = anyone who ever signed in" model collapses these three populations into one bucket and loses two capabilities the portal needs from day one:
 
-- **Pré-provisioning** — an établissement director must be able to assign a scope to a salarié before the salarié first signs in. The salarié needs a portal-side identity that pre-exists their first OIDC callback.
+- **Pré-provisioning** — a structure director must be able to assign a scope to a salarié before the salarié first signs in. The salarié needs a portal-side identity that pre-exists their first OIDC callback.
 - **Person-without-User** — a dossier is held by a bénéficiaire who may never sign in. The dossier still needs to reference a stable Person identifier; later, if the bénéficiaire signs up to portal-facing services, an account is overlaid on top of the existing Person record.
 
-This ADR specifies the portal-side data model that resolves both the ADR-0025 stubs and these business shapes. It deliberately does **not** specify the upstream sync (Pléiades, Acteurs+, membership / dossier feeds) — that is [ADR-0027](#)'s territory. Likewise, the **facet shapes** (Salarié, Élu, Adhérent, Bénéficiaire) attach to a Person but their fields ride alongside their producing sync, so they land with ADR-0027.
+This ADR specifies the portal-side **identity** model. The organisational hierarchy that `@RequireScope` dereferences (`Region`, `Delegation`, `Structure`) is the sibling concern of [ADR-0027](#), kept on a separate timeline because the source-of-truth audit (cascade + acteurs_plus) reshaped that model after ADR-0026 was first drafted. The upstream **sync** of Person rows from Pléiades / Acteurs+ — together with the **facet shapes** (Salarié, Élu, Adhérent, Bénéficiaire) that attach to a Person — is [ADR-0028](#)'s territory.
 
-ADR-0026's scope: the three core tables (`Person`, `User`, `UserScope`) plus the geographic / organisational hierarchy (`Region`, `Delegation`, `Etablissement`) that scope checks dereference today.
+ADR-0026's scope: the three core tables `Person`, `User`, `UserScope`.
 
 ## Decision Drivers
 
 - **`Principal.user.personId` must point at a real, stable identifier** — guards consuming `self`-scoped resources compare against it, and the AI service uses it (hashed) for audit-log joining per [ADR-0024](0024-ai-service-relay-grpc-sse-bridge.md).
 - **Person-without-User** must be a valid state — Pléiades pre-provisioning, dossier beneficiaries, alumni.
-- **`Etablissement.finess`, `.delegationCode`, `.regionCode`** must resolve from a real row, not a hardcoded map — the [ADR-0016](0016-accessibility-baseline-wcag-aa-targeted-aaa.md) panel-tested admin UI will list établissements; the BFF guards traverse the chain on scope checks.
-- **No premature normalisation of facets.** Salarié / Élu / Adhérent / Bénéficiaire schemas track their upstream system; specifying them before the sync ADR ([ADR-0027](#)) lands invites churn. Mark them as deferred and keep ADR-0026 narrow.
-- **Lazy User creation on first sign-in** — the OIDC callback creates the `User` row the first time it sees a new Entra `oid`. This avoids a Pléiades-side dependency before any sign-in works; Pléiades-driven pre-provisioning lands with ADR-0027 and updates the lookup path, not the schema.
+- **No premature normalisation of facets.** Salarié / Élu / Adhérent / Bénéficiaire schemas track their upstream system; specifying them before the sync ADR ([ADR-0028](#)) lands invites churn. Mark them as deferred and keep ADR-0026 narrow.
+- **Lazy User creation on first sign-in** — the OIDC callback creates the `User` row the first time it sees a new Entra `oid`. This avoids a Pléiades-side dependency before any sign-in works; Pléiades-driven pre-provisioning lands with ADR-0028 and updates the lookup path, not the schema.
+- **Safe-by-default dedup.** `entraOid` is the only natural key the v1 provisioner trusts. Email is an attribute, not an identifier — see "Lifecycle" below for why.
 - **No PII outside the boundary it belongs in.** `Person.firstName` / `lastName` are PII — they need the same redaction / hashing posture as the audit-log salt ([ADR-0013](0013-audit-trail-separated-postgres-append-only.md)).
 
 ## Considered Options
@@ -44,7 +43,7 @@ ADR-0026's scope: the three core tables (`Person`, `User`, `UserScope`) plus the
 - **Option A — `User`-only, no `Person`.** A single table for "anyone who ever signed in". Dossiers reference `userId` directly. Bénéficiaires who never sign in have no row at all.
 - **Option B — `Person` golden record + `User` portal-account overlay (chosen).** Two tables, one-to-zero-or-one relationship. `Person` is the stable identity; `User` is the portal-access overlay that exists when (and only when) someone has portal access.
 - **Option C — `Person` lives in Entra (no portal-side row).** Use Entra's user object as the golden record; portal stores only deltas (scopes, etc.).
-- **Option D — `Person` + per-relationship junction (Salarié-of-établissement-X, Élu-of-CD-Y, …) embedded directly in `Person`.** Single table with discriminator columns for every facet.
+- **Option D — `Person` + per-relationship junction (Salarié-of-structure-X, Élu-of-CD-Y, …) embedded directly in `Person`.** Single table with discriminator columns for every facet.
 
 ## Decision Outcome
 
@@ -54,7 +53,7 @@ Chosen option: **B — `Person` golden record + `User` portal-account overlay**,
 2. lets a User row carry portal-only state (`lastSignInAt`, future audit-flagging, future user-preferences in [ADR-0016](0016-accessibility-baseline-wcag-aa-targeted-aaa.md)) without polluting the Person record that Pléiades / Acteurs+ owns;
 3. matches the existing intuition in ADR-0025's `Principal.user.{id, personId}` shape: the two ids exist because the two concerns are distinct.
 
-### Schema — core tables
+### Schema
 
 ```prisma
 model Person {
@@ -62,18 +61,19 @@ model Person {
   // Identity. firstName + lastName are PII; treat per ADR-0013's redact rules.
   firstName   String
   lastName    String
-  // Primary contact email. Unique because it serves as the fallback
-  // dedup key for Pléiades / Acteurs+ syncs (ADR-0027) — a future
-  // sync receiving a Pléiades row with email X looks up Person by
-  // email before deciding insert vs update.
-  email       String?  @unique
+  // Primary contact email. Indexed for operator-driven lookup (admin UI
+  // search, ADR-0028 reconciliation flow), NOT unique — two distinct
+  // humans genuinely can share an email (shared family alias, generic
+  // info@ mailbox at a small partner organisation, error in an upstream
+  // feed). A unique constraint would crash the first Pléiades import
+  // that surfaces such a pair.
+  email       String?
   // Provenance: which upstream owns the row. v1: 'self-signin'
   // (lazy-created at OIDC callback), 'admin-ui' (manually entered
   // by an admin before first sign-in), 'seed' (test-tenant
-  // provisioning).
-  // ADR-0027 will add 'pleiades' and 'acteurs-plus'. The field is
-  // a free-form string in v1; promoting to an enum is an ADR-0027
-  // decision once the sync sources are concrete.
+  // provisioning). ADR-0028 will add 'pleiades' and 'acteurs-plus'.
+  // The field is a free-form string in v1; promoting to an enum is
+  // an ADR-0028 decision once the sync sources are concrete.
   source      String
   // Upstream-system identifier (Pléiades matricule, Acteurs+ id).
   // Nullable because v1 sources do not provide one.
@@ -85,6 +85,7 @@ model Person {
 
   @@index([source])
   @@index([externalId])
+  @@index([email])
 }
 
 model User {
@@ -114,15 +115,15 @@ model UserScope {
   user        User      @relation(fields: [userId], references: [id], onDelete: Cascade)
   // Discriminator — one of the six ADR-0025 scope kinds.
   kind        String
-  // Per-kind payload. FINESS for etablissement, dept code for
-  // delegation, INSEE region code for region, empty string for
-  // self / siege / unrestricted (the unique constraint below
+  // Per-kind payload — semantics owned by ADR-0027. For 'etablissement'
+  // the value is a Structure.code (string); for 'delegation' it is a
+  // Delegation.code; for 'region' it is a Region.code. Empty string for
+  // 'self' / 'siege' / 'unrestricted' (the unique constraint below
   // tolerates empty strings).
   value       String    @default("")
-  // Provenance same posture as Person.source. v1: 'admin-ui' or
-  // 'seed'. ADR-0027 adds 'pleiades' / 'acteurs-plus' and the
-  // reconciliation rules between admin overrides and upstream
-  // data.
+  // Provenance, same posture as Person.source. v1: 'admin-ui' or
+  // 'seed'. ADR-0028 adds 'pleiades' / 'acteurs-plus' and the
+  // reconciliation rules between admin overrides and upstream data.
   source      String
   createdAt   DateTime  @default(now())
   // When non-null and past, the row is ignored at sign-in.
@@ -135,46 +136,7 @@ model UserScope {
 }
 ```
 
-### Schema — organisational hierarchy
-
-```prisma
-model Region {
-  // INSEE region code (2 digits — '11' for Île-de-France, '75' for
-  // Nouvelle-Aquitaine). Stable across reorgs; doubles as the
-  // primary key because the codes are short and stable.
-  code        String   @id
-  name        String
-  delegations Delegation[]
-}
-
-model Delegation {
-  // French department code (2-3 chars — '33', '2A', '971'). Same
-  // rationale as Region.code.
-  code        String   @id
-  name        String
-  regionCode  String
-  region      Region   @relation(fields: [regionCode], references: [code])
-  etablissements Etablissement[]
-}
-
-model Etablissement {
-  // FINESS code (9 digits — '0330800013'). The legal identifier
-  // for medico-social establishments in France; stable across
-  // reorgs.
-  finess        String   @id
-  name          String
-  // What this row is: a real établissement vs the siège vs a
-  // future placeholder. Drives scope matching: the matcher
-  // resolves `principal.scopes` against this column.
-  kind          String   // 'etablissement' | 'siege'
-  delegationCode String
-  delegation    Delegation @relation(fields: [delegationCode], references: [code])
-
-  @@index([delegationCode])
-}
-```
-
-`Region.code` / `Delegation.code` / `Etablissement.finess` doubling as primary keys is a deliberate choice: they are externally-meaningful identifiers that already exist in every upstream system, they appear in URLs (`/api/etablissements/0330800013`), and they round-trip cleanly through scope literals (`etablissement:0330800013`). Adding a separate UUID would force every consumer to indirect through it for no gain.
+`UserScope.value` references the codes defined in [ADR-0027](#) (`Structure.code`, `Delegation.code`, `Region.code`) but stores them as opaque strings — no foreign-key from `UserScope` to those tables. Rationale: a scope can outlive its target (a structure decommissioned mid-quarter still has historical UserScope rows referencing its code, useful for the audit log). The admin UI surface that creates UserScope rows validates the code against ADR-0027's tables at write time; the runtime guard does the same dereference at sign-in.
 
 ### Lifecycle — Person + User creation
 
@@ -188,24 +150,27 @@ model Etablissement {
    │   2. PersonAndUserProvisioner.ensureUser({ oid: X, … })  │
    │      a. Look up User by entraOid                         │
    │         → if found: update lastSignInAt, return          │
-   │         → if not found: continue                         │
-   │      b. Look up Person by email (case-insensitive)       │
-   │         → if found: link User to existing Person         │
-   │         → if not found: create Person with                │
-   │           source='self-signin', then link User           │
+   │         → if not found: create a fresh Person + linked   │
+   │           User in one transaction.                        │
+   │           Person.source = 'self-signin'                  │
+   │           Person.firstName / lastName = split(Entra      │
+   │             displayName) — best effort                   │
+   │           Person.email = Entra preferred_username        │
    │   3. PrincipalBuilder.build() now sees a real Person     │
    │      and a real User; Principal.user.personId carries    │
    │      Person.id rather than the entraOid placeholder      │
    └──────────────────────────────────────────────────────────┘
 ```
 
-**ADR-0027 (later):** Pléiades / Acteurs+ syncs create Person rows ahead of any sign-in. The lookup path becomes:
+**Why no email-based merging in v1.** Two distinct people genuinely can share an email (shared family alias, generic `info@` mailbox at a small partner organisation, error in an upstream feed). Auto-merging a fresh sign-in into an existing Person by email match would silently corrupt the golden record without surfacing a conflict. v1 takes the safe-by-default posture: `entraOid` is the only natural key the provisioner trusts; every other dedup happens on the explicit reconciliation flow that ships with ADR-0028.
 
-1. by `Person.externalId` if the sign-in carries one (rare — only when the federated identity exposes the upstream id),
-2. by `Person.email` (the existing v1 lookup),
-3. fallback to creating a `source='self-signin'` Person.
+**ADR-0028 (later).** Pléiades / Acteurs+ syncs create Person rows ahead of any sign-in. The provisioner's lookup path extends, in order:
 
-The schema does not change; only the provisioner's lookup order extends.
+1. by `Person.externalId` when the sign-in carries one (only when the federated identity exposes the upstream id, or when an admin has linked the two via the admin UI),
+2. by an explicit operator-driven match flow on `Person.email` — surfacing the candidate match for confirmation rather than auto-merging,
+3. fallback to creating a `source='self-signin'` Person — same as v1.
+
+The schema does not change between the two regimes; only the provisioner's logic and the conflict-resolution UI extend.
 
 ### Scope resolution — `PrismaScopeResolver`
 
@@ -232,6 +197,8 @@ export class PrismaScopeResolver extends ScopeResolver {
 
 The signature `resolve({ userId })` differs from the current `resolve({ entraOid })` — the User UUID is the natural key once the schema exists. The PrincipalBuilder evolves to pass `userId` instead, which is fine because the provisioner above has just created / fetched it.
 
+The full guard-side dereference path (`principalCoversResource` walking `Structure.delegationCode` → `Delegation.regionCode` → `Region`) requires ADR-0027's hierarchy to be live. PR sequencing reflects this — see "More Information" below.
+
 ### `Principal.user` post-implementation
 
 The two placeholders called out at the top of this ADR resolve:
@@ -244,34 +211,33 @@ The two placeholders called out at the top of this ADR resolve:
 | `user.tenantId`    | Entra `tid`         | unchanged                                                |
 | `user.displayName` | Entra `displayName` | unchanged (cached at sign-in; admins can override later) |
 
-### What ADR-0026 ships vs what stays for ADR-0027
+### What ADR-0026 ships vs adjacent ADRs
 
-| Concern                                                                     | ADR-0026 (this)              | ADR-0027 (next)          |
-| --------------------------------------------------------------------------- | ---------------------------- | ------------------------ |
-| `Person`, `User`, `UserScope` schema                                        | ✅                           | —                        |
-| `Region`, `Delegation`, `Etablissement` schema                              | ✅ (manually-seeded in v1)   | Pléiades-sync population |
-| `Person.source = 'self-signin'` lazy creation                               | ✅                           | —                        |
-| `Person.source = 'pleiades'` / `'acteurs-plus'`                             | as a documented future value | Sync implementation      |
-| Salarié / Élu / Adhérent / Bénéficiaire facets                              | deferred                     | ✅                       |
-| Reconciliation between admin-UI overrides and Pléiades-driven `user_scopes` | deferred                     | ✅                       |
+| Concern                                                                   | ADR-0026 (this)              | ADR-0027 (org hierarchy) | ADR-0028 (sync + facets) |
+| ------------------------------------------------------------------------- | ---------------------------- | ------------------------ | ------------------------ |
+| `Person`, `User`, `UserScope` schema                                      | ✅                           | —                        | —                        |
+| `Region`, `Delegation`, `Structure` schema                                | —                            | ✅                       | —                        |
+| `Person.source = 'self-signin'` lazy creation                             | ✅                           | —                        | —                        |
+| `Person.source = 'pleiades'` / `'acteurs-plus'`                           | as a documented future value | —                        | Sync implementation      |
+| Salarié / Élu / Adhérent / Bénéficiaire facets                            | deferred                     | —                        | ✅                       |
+| Reconciliation between admin-UI overrides and upstream-driven user_scopes | deferred                     | —                        | ✅                       |
 
 The facet split was the main "tempting to ship now" item; deferring it keeps the schema migration small enough to land + roll back cleanly if the lazy-provisioner exposes a corner case.
 
 ### Consequences
 
 - Good, because `Principal.user.personId` is finally a real, stable identifier — `@RequireScope({ kind: 'self' })` can compare against `Dossier.personId` end-to-end without "the entraOid happens to be the personId" gymnastics.
-- Good, because Pléiades and Acteurs+ syncs (ADR-0027) can drop into a known shape; their lookup logic (email-based dedup, externalId carryover) is already part of v1.
+- Good, because Pléiades and Acteurs+ syncs (ADR-0028) drop into a known shape; their reconciliation logic (`externalId` precedence, operator-surfaced email-based candidates) extends the v1 provisioner rather than rewriting it.
 - Good, because the admin UI scope-seeding flow (v1 manual entry per ADR-0025 §"Sources of truth — apf_portal-side `user_scopes` table") now has a target row to write against (`UserScope`).
-- Bad, because `Person.email` as the v1 dedup key is fragile — two Pléiades records with the same email crash the unique constraint. Mitigation: ADR-0027 adds `externalId` precedence and surfaces conflicts to the operator.
 - Bad, because lazy-create-at-sign-in produces a Person row with sparse fields (`firstName` / `lastName` from the Entra `displayName` split, no postal address, no phone). Acceptable for v1 since dossiers / RH consumers do not exist yet; reconciliation with Pléiades data at sync time fills the gaps.
-- Neutral, because `Region.code` / `Delegation.code` / `Etablissement.finess` as primary keys preclude renames. APF's INSEE codes are stable; if a délégation merges, the row is deleted + a new one is inserted with the new code. The cost is well-bounded.
+- Bad, because a user who signs in once with an Entra account and later gets imported from Pléiades produces two Person rows (one `self-signin`, one `pleiades`) that look like the same human. ADR-0028 handles the merge as an operator-confirmed flow; v1 simply accepts the duplicate as the cost of safe-by-default dedup. The duplicate is observable (same email) and easy to surface, not hidden.
+- Neutral, because `UserScope.value` is an opaque string with no FK to ADR-0027's hierarchy tables. The write path validates against those tables; runtime read tolerates stale codes. Stale entries do not crash sign-in — they fail the `principalCoversResource` check on the resource that no longer exists, which is the correct behaviour.
 
 ### Confirmation
 
 - **Migration tests.** Prisma migration emits a SQL file; the `infra/local` dev stack runs it on fresh boot. Manual + a small `e2e` spec exercising the lazy-create path with a stubbed Entra response.
-- **PrismaScopeResolver integration test.** Two personas (one with `etablissement:0330800013`, one with `unrestricted`) signed in, scopes round-trip from DB → Principal → `principalCoversResource`.
+- **PrismaScopeResolver integration test.** Two personas signed in (one with a `kind='etablissement'` scope, one with `kind='unrestricted'`), scopes round-trip from DB → Principal → `principalCoversResource`. Requires ADR-0027's seeded hierarchy to give the etablissement-scoped persona a real `Structure.code` to point at.
 - **`Person.source` enum-as-string is single-sourced.** A small constant array in `apps/portal-bff/src/users/person-source.ts` lists the legal values; the catalogue-drift gate ([ADR-0025 §"Confirmation"](0025-authorization-model-privileges-roles-scopes.md)) extends to assert every string written to `Person.source` is in the catalogue. Same posture as the `Privilege` / `FunctionalRole` catalogues.
-- **`Etablissement.kind` enum-as-string.** Same posture as `Person.source`. Legal values: `'etablissement'`, `'siege'`. Extending to `'preprod-placeholder'` etc. is an ADR amendment.
 
 ## Pros and Cons of the Options
 
@@ -281,7 +247,7 @@ The facet split was the main "tempting to ship now" item; deferring it keeps the
 - Good, because portal-only fields (`lastSignInAt`, future a11y preferences, future audit flags) ride on `User`, not on the shared Person record that Pléiades may overwrite.
 - Good, because the ADR-0025 stubs resolve naturally — `personId` ≠ `userId` reflects the two-concern split that was already designed in.
 - Bad, because two tables means two queries on the OIDC callback hot path. Mitigation: a single Prisma `include` keeps it to one round trip.
-- Neutral, because reconciling lazy-created Person rows with later Pléiades data needs a documented merge policy — that policy is ADR-0027's territory and is easier to design with this shape than with Option A.
+- Neutral, because reconciling lazy-created Person rows with later Pléiades data needs a documented merge policy — that policy is ADR-0028's territory and is easier to design with this shape than with Option A.
 
 ### Option A — `User`-only
 
@@ -300,17 +266,18 @@ The facet split was the main "tempting to ship now" item; deferring it keeps the
 ### Option D — `Person` + embedded facet columns
 
 - Good, because one less join when reading "the salarié record for Person X".
-- Bad, because `Person.salarie_etablissement_id`, `Person.elu_mandat_type`, `Person.adherent_cotisation_status`, … each introduce a NULL column that 95% of rows leave unused — schema bloat without normalization gains.
+- Bad, because `Person.salarie_structure_id`, `Person.elu_mandat_type`, `Person.adherent_cotisation_status`, … each introduce a NULL column that 95% of rows leave unused — schema bloat without normalization gains.
 - Bad, because Pléiades data shape evolves independently from Acteurs+ data shape; embedding both in `Person` means every Pléiades schema change touches the table Acteurs+ rows also live in. Separate facet tables ride their own sync's lifecycle.
 
 ## More Information
 
-**Phasing.** This ADR is decision-only. Implementation lands in two PRs once the ADR is accepted:
+**Phasing.** This ADR is decision-only. Implementation is sequenced against [ADR-0027](#) because the PrismaScopeResolver test matrix needs real `Structure.code` / `Delegation.code` / `Region.code` rows:
 
-1. **PR — Prisma schema + lazy provisioner.** `Person`, `User`, `Region`, `Delegation`, `Etablissement`, `UserScope` models; `PersonAndUserProvisioner` called from `SessionEstablisher`; `Person.source` + `Etablissement.kind` constants + drift-gate extension; updated `PrincipalBuilder` to populate `Principal.user.{id, personId}` from the real rows.
-2. **PR — `PrismaScopeResolver` + admin UI scope-seeding screen + test-tenant seed.** Replaces `StubScopeResolver` in the AuthModule. Seeds the 19 test personas' `user_scopes` rows per `notes/test-tenant-role-assignments.md`. Adds an `/admin/users/:id/scopes` admin-app screen for manual scope management.
+1. **PR — Prisma schema + lazy provisioner.** `Person`, `User`, `UserScope` models; `PersonAndUserProvisioner` called from `SessionEstablisher`; `Person.source` constants + drift-gate extension; updated `PrincipalBuilder` to populate `Principal.user.{id, personId}` from the real rows. Independent of ADR-0027 — can ship in parallel.
+2. **PR — `PrismaScopeResolver` + admin UI scope-seeding screen + test-tenant seed.** Replaces `StubScopeResolver` in the AuthModule. Seeds the 19 test personas' `user_scopes` rows per `notes/test-tenant-role-assignments.md`. Adds an `/admin/users/:id/scopes` admin-app screen for manual scope management. **Depends on ADR-0027 PR 1** — the seed references `Structure.code` values that must already exist in the database.
 
 **Follow-up ADRs.**
 
-- **[ADR-0027](#) — Pléiades + Acteurs+ syncs + facet schemas.** Specifies how `Person` rows are populated from upstream, how facets attach (`Salarie`, `Adherent`, `Benevole`, `Elu`, `Beneficiaire`, `PartenaireExterne`), the reconciliation policy between sync-owned and admin-UI-owned fields, and how `user_scopes` is computed from facet relationships.
+- **[ADR-0027](#) — Portal-side organisational hierarchy.** `Region` / `Delegation` / `Structure` schema (Structure with kind discriminator + nullable FINESS / SIRET keys, cascade-aligned). Sibling to ADR-0026, shipped at the same cadence.
+- **[ADR-0028](#) — Pléiades + Acteurs+ syncs + facet schemas.** Specifies how `Person` rows are populated from upstream, how facets attach (`Salarie`, `Adherent`, `Benevole`, `Elu`, `Beneficiaire`, `PartenaireExterne`), the reconciliation policy between sync-owned and admin-UI-owned fields, and how `user_scopes` is computed from facet relationships.
 - **A future ADR — time-bound roles.** `UserScope.expiresAt` already exists; the corresponding facet-level mechanism (interim director for two months, treasurer mandate from 2026 to 2029) lands when the use case is concrete.