Add SQLAlchemy persistence layer

docs/backlog/01_execution_backlog.md

@@ -28,9 +28,9 @@
 
 ## Package C: Persistence
 
-- [ ] SQLAlchemy models
-- [ ] repositories for PostgreSQL/SQLite
-- [ ] migrations
+- [x] SQLAlchemy models
+- [x] repositories for PostgreSQL/SQLite
+- [x] migrations
 - [ ] artifact metadata persistence
 - [ ] event store queries with pagination
 

docs/storage/01_schema.md

@@ -5,6 +5,19 @@
 - production: PostgreSQL
 - local development: SQLite
 
+## Persistence Path In Code
+
+SQLAlchemy adapter реализован в:
+
+- [src/ai_orchestrator/infrastructure/storage/sqlalchemy.py](/Z:/codex/ai_orchestrator/src/ai_orchestrator/infrastructure/storage/sqlalchemy.py)
+- [src/ai_orchestrator/infrastructure/storage/factory.py](/Z:/codex/ai_orchestrator/src/ai_orchestrator/infrastructure/storage/factory.py)
+
+Migration skeleton:
+
+- [alembic.ini](/Z:/codex/ai_orchestrator/alembic.ini)
+- [migrations/env.py](/Z:/codex/ai_orchestrator/migrations/env.py)
+- [migrations/versions/0001_initial_schema.py](/Z:/codex/ai_orchestrator/migrations/versions/0001_initial_schema.py)
+
 ## Tables
 
 ### projects
@@ -156,3 +169,8 @@
 - `confirmations(status, created_at)`
 - `worker_sessions(status, last_heartbeat_at)`
 
+## Active Adapter Strategy
+
+- `memory` backend остается для быстрых unit/integration прогонов;
+- `sqlite` backend предназначен для локального development без Docker;
+- `postgres` backend является production target.