Removes the unused GET /api/activities list/detail endpoints, moves the
review-queue list and resolve/unlock/unassign actions under
/api/activities, renames resolve to assign end-to-end, and drops the
now-unused store.ReviewQueue helper.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
HTTP-level counterpart to the store-layer isolation tests: proves the full
middleware+handler chain rejects/hides another user's activities, workout
kinds, and review queue even when given that user's real row ids, and that
an unprovisioned session is blocked from every data route.