chore: add docker-compose.prod.yml production override

Removes --reload from uvicorn, adds restart: unless-stopped to all
services, bumps uvicorn to 2 workers.

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

docker-compose.prod.yml

@@ -0,0 +1,32 @@
+# Production overrides — use with:
+#   docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d --build
+#
+# Changes from dev:
+#   - uvicorn runs without --reload
+#   - all services restart unless stopped
+#   - worker concurrency bumped to match a typical host
+
+services:
+  postgres:
+    restart: unless-stopped
+
+  redis:
+    restart: unless-stopped
+
+  api:
+    command: >
+      sh -c "alembic upgrade head &&
+             uvicorn app.main:app --host 0.0.0.0 --port 8000 --workers 2"
+    restart: unless-stopped
+
+  worker:
+    restart: unless-stopped
+
+  beat:
+    restart: unless-stopped
+
+  frontend:
+    restart: unless-stopped
+
+  nginx:
+    restart: unless-stopped