[P3] POST /api/pr-fix-queue/requeue has no route.test.ts coverage, breaking the #416 co-located-test convention

[itsmiso-ai]

Ask: Add a co-located route.test.ts for POST /api/pr-fix-queue/requeue covering auth, parse validation, the not-found path, and the happy requeue.

Expected files: src/app/api/pr-fix-queue/requeue/route.test.ts, src/app/api/pr-fix-queue/requeue/route.ts

Problem: POST /api/pr-fix-queue/requeue is the only mutating API route under src/app/api/ without a co-located route.test.ts (excluding src/app/api/auth/[...nextauth], which is NextAuth's own handler). It is mutating (calls requeuePrFixItem over prisma, performs a status transition, and writes audit history). It is also a recently-introduced feature (commit 8790ae7 "Route BLOCKED PR-fix items into NEEDS_HUMAN lane and add a requeue action"), so its surface is not yet battle-tested and there is no regression net. Issue #416 set the co-located-test convention that every other route follows; this one slipped. The route's input parser (parseRequeuePrFixInput) is reached in many places (requeue from operator UI, automated tombstones), and a parse-error regression here would block the entire pr-fix-surfacing pipeline.

Evidence:

• src/app/api/pr-fix-queue/requeue/route.ts has auth, enforceRateLimit, parseRequeuePrFixInput, requeuePrFixItem, and prisma — but no route.test.ts alongside it.
• Running find src/app/api -name 'route.ts' returns 59 files; find src/app/api -name 'route.test.ts' returns 57. The only missing tests are requeue (mutating) and auth/[...nextauth] (NextAuth handler — exempt).
• AGENTS.md and the labels.yaml workflow establish the co-located-test convention. Issue Add co-located route.test.ts for the 17 routes currently uncovered, prioritized by data-leak risk (/api/audit, /api/auto #416 originally filed this gap for 17 routes; [P3] New POST /api/issues/label route writes GitHub labels with no route.test.ts coverage #803 closed the last mutating-route gap for label — requeue is the new gap.
• The requeue path is the recovery action for tombstoned BLOCKED pr-fix items (per issue PR-fix items marked BLOCKED cannot be requeued: route them to NEEDS_HUMAN and add a requeue action #771); a regression here strands the queue item until a manual DB edit.

Acceptance: Add src/app/api/pr-fix-queue/requeue/route.test.ts covering: 401 unauthenticated, 400 invalid JSON, 400 parse error (missing fields), 404 item not found, 200 happy path (requeuePrFixItem returns the item, JSON response includes the item). Test must run green under npm test and follow the same vi.mock pattern used by neighbouring pr-fix-queue tests.

[itsmiso-ai]

Groomed: ready for work. The test should mirror the vi.mock setup in src/app/api/pr-fix-queue/mark/route.test.ts and src/app/api/pr-fix-queue/enqueue/route.test.ts, using helpers from src/test/route-helpers.ts. Acceptance: 401 unauthenticated, 400 invalid JSON, 400 parse error, 404 not found, 200 happy path — all green under npm test.