docs(10-02): complete admin backend contract plan

.planning/ROADMAP.md

@@ -424,7 +424,7 @@ Plans:
   3. The Collections form's relation manager lets an admin search, link and unlink an editor.
   4. API calls in the SPA use TypeScript types generated from the OpenAPI document, with no hand-maintained duplicate type.
 
-**Plans**: 1/5 plans executed
+**Plans**: 2/5 plans executed
 **UI hint**: yes
 
 Plans:
@@ -433,7 +433,7 @@ Plans:
 - [x] 10-01-PLAN.md — Tracer: backend.uri prefix, cookie+CSRF transport, embedded SPA (login, navigation, typed Genres list), framework admin OpenAPI pipeline, fonoteka lang/icons/Collections nav
 
 **Wave 2** *(blocked on Wave 1 completion)*
-- [ ] 10-02-PLAN.md — Backend contract: relation options and saves with labels, backend strings bundle and overrides, messages, declarative toolbar, filter options, fully typed OpenAPI with conformance
+- [x] 10-02-PLAN.md — Backend contract: relation options and saves with labels, backend strings bundle and overrides, messages, declarative toolbar, filter options, fully typed OpenAPI with conformance
 
 **Wave 3** *(blocked on Wave 2 completion)*
 - [ ] 10-03-PLAN.md — SPA lists, forms, filter bar and settings screen for all five controllers
@@ -547,7 +547,7 @@ Phases execute in numeric order: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 →
 | 7. User plugin and authentication | 8/8 | Complete    | 2026-09-23 |
 | 8. OAuth2.1 authorization server | 10/10 | Complete   | 2026-09-23 |
 | 9. Backend admin authentication and schema pipeline | 12/12 | In Progress|  |
-| 10. Admin Vue SPA | 1/5 | In Progress|  |
+| 10. Admin Vue SPA | 2/5 | In Progress|  |
 | 11. Jobs, realtime and search infrastructure | 0/TBD | Not started | - |
 | 12. Płytarium API — Collections and Albums | 0/TBD | Not started | - |
 | 13. Płytarium API — wishlist, notifications, CSV, credentials, public routes | 0/TBD | Not started | - |