Julien Gautier
377a484afc
The narrowing test for `isStructureKind` had `const candidate: string = 'medico_social'`, which ESLint's `@typescript-eslint/no-inferrable-types` correctly flags as trivially-inferred. The naive fix - dropping the annotation - would let TypeScript infer the literal type `'medico_social'`, which is already a StructureKind subtype. The narrowing check would then be vacuous (TypeScript already knows the value is a kind, the runtime guard has nothing to prove). Fix: round-trip through `String()` to widen the literal to `string`. TypeScript infers `string` for `String(...)` return; no annotation needed; the narrowing test stays meaningful. CI lint target on portal-bff now passes 0 errors. The 13 remaining warnings (non-null assertions in principal-extractor.spec, unused underscored params in rate-limit.middleware, etc.) are pre-existing and not in scope for this fix.