feat(WP-0004): railiance deployment & service ops

- Dockerfile (multi-stage, uv-based, slim runtime)
- .dockerignore
- docker-compose.railiance.yml (Temporal + NATS + PG, no Elasticsearch)
- GET /health endpoint (db + temporal probes, 200/503)
- .env.example (complete env var reference)
- Makefile: migrate, sync-all, dev-up/down, railiance-up/down,
  start-worker, start-api, start-event-router, help targets;
  extracted sync-event-types Python to scripts/sync_event_types.py
- SIGTERM graceful shutdown in worker.py and event_router.py
- docs/runbook.md: Railiance deployment section

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

src/activity_core/worker.py

@@ -26,6 +26,7 @@ from __future__ import annotations
 import asyncio
 import logging
 import os
+import signal
 
 from temporalio.client import Client
 from temporalio.runtime import PrometheusConfig, Runtime, TelemetryConfig
@@ -102,12 +103,21 @@ async def run() -> None:
         activities=[persist_task_instance],
     )
 
+    loop = asyncio.get_running_loop()
+    stop = asyncio.Event()
+    loop.add_signal_handler(signal.SIGTERM, stop.set)
+    loop.add_signal_handler(signal.SIGINT, stop.set)
+
     async with orchestrator_worker, task_worker:
-        print(
-            f"Workers running — queues: {ORCHESTRATOR_TASK_QUEUE!r}, "
-            f"{TASK_EXECUTION_TASK_QUEUE!r} (namespace={TEMPORAL_NAMESPACE!r})"
+        logger.info(
+            "Workers running — queues: %r, %r (namespace=%r)",
+            ORCHESTRATOR_TASK_QUEUE,
+            TASK_EXECUTION_TASK_QUEUE,
+            TEMPORAL_NAMESPACE,
         )
-        await asyncio.Future()  # run until cancelled
+        await stop.wait()
+        logger.info("Shutdown signal received — draining workers")
+    logger.info("Workers stopped cleanly")
 
 
 if __name__ == "__main__":