chore: track Nx 22 AI tooling artefacts injected by generators

Nx 22 generators inject AI agent tooling into the repo via marked
sections and side files. Rather than re-deleting them after every
generator run, track the workspace-level ones and document why.

- CLAUDE.md gains a 'General Guidelines for working with Nx' section
  between Nx-managed markers; future Nx versions will update this
  section automatically without touching our project rules above.
  Pre-existing prettier-formatted blank lines added before code blocks
  are kept.
- .claude/settings.json (228 bytes) enables the nx-claude-plugins
  marketplace from nrwl/nx-ai-agents-config; tracked for contributor
  consistency. The personal .claude/settings.local.json stays
  gitignored.
- .github/ is the Nx AI skills/prompts/agents catalog. Kept despite
  being GitHub-named; it does not conflict with our Gitea workflows
  which will live under .gitea/workflows/ (per ADR-0015).
- .gitignore picks up Nx-managed transient dirs (.nx/polygraph,
  .claude/worktrees) and a trailing newline fix.

AGENTS.md is removed: it duplicated only the Nx auto-injected guidance
that CLAUDE.md already carries (CLAUDE.md is the strictly broader file
- project rules + Nx section). One source of truth for AI-agent
guidance.

.github/skills/nx-import/references/ESLINT.md

@@ -0,0 +1,109 @@
+## ESLint
+
+ESLint-specific guidance for `nx import`. For generic import issues (root deps, pnpm globs, project references), see `SKILL.md`.
+
+---
+
+### How `@nx/eslint/plugin` Works
+
+`@nx/eslint/plugin` scans for ESLint config files and creates a lint target for each project. It detects **both** flat config files (`eslint.config.{js,mjs,cjs,ts,mts,cts}`) and legacy config files (`.eslintrc.{json,js,cjs,mjs,yml,yaml}`).
+
+**Plugin options (set during `nx add @nx/eslint`):**
+
+```json
+{
+  "plugin": "@nx/eslint/plugin",
+  "options": {
+    "targetName": "eslint:lint"
+  }
+}
+```
+
+**Auto-installation**: `nx import` auto-detects ESLint config files and offers to install `@nx/eslint`. Accept the offer — it registers the plugin and updates `namedInputs.production` to exclude ESLint config files.
+
+---
+
+### Duplicate `lint` and `eslint:lint` Targets
+
+After import, projects will have **two** lint-related targets if the source `package.json` has a `"lint"` npm script:
+
+- `eslint:lint` — inferred by `@nx/eslint/plugin`; has proper caching and input/output tracking
+- `lint` — created by Nx from the npm script via `nx:run-script`; no caching intelligence, just wraps `npm run lint`
+
+**Fix**: Remove the `"lint"` script from each project's `package.json`. Keep `"lint:fix"` if present — there is no plugin-inferred equivalent for auto-fixing.
+
+---
+
+### Legacy `.eslintrc.*` Configs Linting Generated Files
+
+When `@nx/eslint/plugin` runs `eslint .` on a project with a legacy `.eslintrc.*` config that uses `parserOptions.project`, it tries to lint **all** files in the project directory including:
+
+- Generated `dist/**/*.d.ts` files (not in tsconfig `include`)
+- The `.eslintrc.js` config file itself (not in tsconfig `include`)
+
+This causes `Parsing error: ESLint was configured to run on X using parserOptions.project, however that TSConfig does not include this file`.
+
+**Fix**: Add `ignorePatterns` to the `.eslintrc.*` config:
+
+```json
+// .eslintrc.json
+{
+  "ignorePatterns": ["dist/**"]
+}
+```
+
+```js
+// .eslintrc.js — also ignore the config file itself since module.exports isn't in tsconfig
+module.exports = {
+  ignorePatterns: ['dist/**', '.eslintrc.js'],
+  // ...
+};
+```
+
+---
+
+### Flat Config `.cjs` Files Self-Linting
+
+When a project uses `eslint.config.cjs` (CJS flat config), `eslint .` lints the config file itself. The `require()` call on line 1 triggers `@typescript-eslint/no-require-imports`.
+
+**Fix**: Add the config filename to the top-level `ignores` array:
+
+```js
+module.exports = tseslint.config(
+  {
+    ignores: ['dist/**', 'node_modules/**', 'eslint.config.cjs'],
+  },
+  // ...
+);
+```
+
+The same applies to `eslint.config.js` in a CJS project (no `"type": "module"`) if it uses `require()`.
+
+---
+
+### `typescript-eslint` Version Conflict With ESLint 9
+
+`typescript-eslint@7.x` declares `peerDependencies: { "eslint": "^8.56.0" }`, but it is commonly used alongside `"eslint": "^9.0.0"`. npm treats this as a hard peer dep conflict and refuses to install.
+
+**Root cause**: `@nx/eslint` init adds `eslint@~8.57.0` at the workspace root (for its own peer deps). Workspace packages that request `eslint@^9.0.0` + `typescript-eslint@^7.0.0` trigger the conflict when npm resolves their deps.
+
+**Fix**: Upgrade `typescript-eslint` from `^7.0.0` to `^8.0.0` directly in the affected workspace package's `package.json`. The `tseslint.config()` API and `tseslint.configs.recommended` are identical between v7 and v8 — no config changes needed.
+
+```json
+// packages/my-package/package.json
+{
+  "devDependencies": {
+    "typescript-eslint": "^8.0.0"
+  }
+}
+```
+
+**Note**: npm's root-level `"overrides"` field does not force versions for workspace packages' direct dependencies — update each package.json individually.
+
+---
+
+### Mixed ESLint v8 and v9 in One Workspace
+
+Legacy v8 and flat-config v9 packages can coexist in the same workspace. Each package resolves its own `eslint` version. The root `eslint@~8.57.0` (added by `@nx/eslint` init) is used by legacy v8 packages; v9 packages get their own hoisted `eslint@9`.
+
+`@nx/eslint/plugin` infers `eslint:lint` targets for **both** config formats. Legacy packages run ESLint v8 with `.eslintrc.*`; flat-config packages run ESLint v9 with `eslint.config.*`. No special nx.json configuration is needed to support both simultaneously.