docs(09-10): complete collections relation manager plan

.planning/STATE.md

@@ -5,17 +5,17 @@ milestone_name: milestone
 current_phase: 09
 current_phase_name: Backend admin authentication and schema pipeline
 status: executing
-stopped_at: Completed 09-09-PLAN.md
-last_updated: "2026-09-26T13:09:59.401Z"
+stopped_at: Completed 09-10-PLAN.md
+last_updated: "2026-09-26T19:35:51.309Z"
 last_activity: 2026-09-26
-last_activity_desc: Phase 09 execution continued through the Styles controller
-state_head: e9c07223376519f1636dad557cccb6cf0ddd1604
+last_activity_desc: Phase 09 execution continued through Collections and the typed relation manager
+state_head: 12081c153464a632d3a89385f915571a9a14c910
 progress:
   total_phases: 15
   completed_phases: 8
   total_plans: 67
-  completed_plans: 64
-  percent: 96
+  completed_plans: 65
+  percent: 97
 ---
 
 # Project State
@@ -30,11 +30,11 @@ See: .planning/PROJECT.md (updated 2026-09-16)
 ## Current Position
 
 Phase: 09 (Backend admin authentication and schema pipeline) — EXECUTING
-Plan: 10 of 12
+Plan: 11 of 12
 Status: Ready to execute
 Last activity: 2026-09-26
 
-Progress: [██████████] 96%
+Progress: [██████████] 97%
 
 ## Performance Metrics
 
@@ -119,6 +119,7 @@ Progress: [██████████] 96%
 | Phase 09 P07 | 2h20m | 2 tasks | 9 files |
 | Phase 09 P08 | 2h28m | 2 tasks | 4 files |
 | Phase 09 P09 | 11h 48m | 2 tasks | 9 files |
+| Phase 09 P10 | 2h 20m | 3 tasks | 17 files |
 
 ## Accumulated Context
 
@@ -308,6 +309,7 @@ Recent decisions affecting current work:
 - [Phase 09]: The tracked Style source declares no dropdown provider or filter, so production YAML stays exact while isolated compiler fixtures prove typed scalars and provider rejection
 - [Phase 09]: Style slug retains the tracked update-only readonly schema and is generated on create by the model lifecycle
 - [Phase 09]: Style equal-value list ordering is explicitly stabilized by the shared primary-key tie-breaker
+- [Phase 09]: Collection-specific pivot identifiers and stamps remain plugin-owned behind a typed relation contract. — Cabana can validate and execute relations generically without hardcoding Fonoteka tables, columns, roles, or payload behavior.
 
 ### Pending Todos
 
@@ -330,6 +332,6 @@ Items acknowledged and carried forward from previous milestone close:
 
 ## Session Continuity
 
-Last session: 2026-09-26T13:09:59.379Z
-Stopped at: Completed 09-09-PLAN.md
+Last session: 2026-09-26T19:35:51.276Z
+Stopped at: Completed 09-10-PLAN.md
 Resume file: None