feat(service): add FastAPI agent service with 5 routers and Docker setup

- config.py: pydantic-settings with all env vars, privacy mode, per-agent overrides
- app_state.py: global singletons (pool, master agent, registry, llm_router, sweep)
- main.py: FastAPI lifespan startup — DB pool, LLM router, Odoo client, agents, master
- routers/dispatch.py: POST /dispatch with rate limiting and webhook secret auth
- routers/approval.py: GET /approval/pending, POST /approval/respond
- routers/registry.py: GET/POST /registry/agents, POST /registry/backend overrides
- routers/sweep.py: POST /sweep trigger, GET /sweep/status
- routers/health.py: GET /health, GET /health/detailed (DB/Odoo/Ollama checks)
- requirements.txt: pinned deps (fastapi, uvicorn, asyncpg, anthropic, alembic)
- Dockerfile: python:3.11-slim, single uvicorn worker
- docker-compose.yml: agent-service + postgres:15, bound to 192.168.2.47:8001

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

requirements.txt

@@ -0,0 +1,11 @@
+fastapi==0.115.0
+uvicorn[standard]==0.30.6
+pydantic==2.9.2
+pydantic-settings==2.5.2
+asyncpg==0.29.0
+anthropic==0.34.2
+httpx==0.27.2
+alembic==1.13.3
+sqlalchemy[asyncio]==2.0.35
+json-log-formatter==0.5.2
+python-dotenv==1.0.1