Get Entitlements
Return the flat entitlement map for the current user.
Frontend EntitlementsProvider calls this once at app mount. The values come from Redis cache (60s TTL) keyed by user.id.
Auth: Supabase Bearer JWT only. Reading your own plan’s feature matrix is allowed for every signed-in user regardless of programmatic-API-access status.
Programmatic SDK consumers that need their own entitlements should
introspect via /v1/keys/me or the key-bootstrap payload — those
paths already pass the API-access gate they legitimately need to.
The handler acquires a DB session lazily — only on a Redis cache miss that requires recomputing the entitlements snapshot — so the common cache-hit path consumes zero DB connections.