Create sub-resource API endpoints for /users/me/loyalty-programs to allow listing, adding, updating, and removing individual loyalty programs associated with a user, backed by a JSONB array on user_profiles.
## Endpoints Sub-resource API backed by the `loyalty_programs` JSONB array on `user_profiles`. | Method | Path | Description | |--------|------|-------------| | `GET` | `/users/me/loyalty-programs` | List all programs | | `POST` | `/users/me/loyalty-programs` | Add a program | | `PATCH` | `/users/me/loyalty-programs/:id` | Update a program | | `DELETE` | `/users/me/loyalty-programs/:id` | Remove a program | ## Notes - Element `id` is a client-supplied UUID included in the POST body. - No `is_primary` logic; no cross-user visibility. - Full OpenAPI documentation required. **Reference:** `documentation/features/users.md` — Loyalty Programs section