feat: single container image (nginx + backend), fix fresh DB init

- deploy/Dockerfile: unified image with supervisord (nginx + uvicorn)
- distribution/docker-compose.single.yml: single container option
- distribution/README.md: 3 deployment options (single, compose, docker run)
- Fix: add status column to chat_messages CREATE TABLE (was only in migration, broke fresh DB)
- push-images.sh: builds 3 images (unified, backend, frontend)

distribution/docker-compose.single.yml

@@ -0,0 +1,31 @@
+services:
+  agent:
+    image: ${OCIR_REGION}.ocir.io/${OCIR_NAMESPACE}/oci-cis-agent:${IMAGE_TAG:-latest}
+    container_name: oci-cis-agent
+    restart: unless-stopped
+    environment:
+      - APP_SECRET=${APP_SECRET:?Set APP_SECRET in .env (openssl rand -hex 64)}
+      - JWT_EXPIRY_HOURS=${JWT_EXPIRY_HOURS:-12}
+      - DATA_DIR=/data
+      - CORS_ORIGINS=${CORS_ORIGINS:-}
+      - TZ=${TZ:-America/Sao_Paulo}
+      - OCI_CLI_SUPPRESS_FILE_PERMISSIONS_WARNING=True
+    ports:
+      - "${PORT:-8080}:8080"
+    volumes:
+      - agent-data:/data
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:8080/api/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+    logging:
+      driver: "json-file"
+      options:
+        max-size: "10m"
+        max-file: "3"
+    mem_limit: 4g
+
+volumes:
+  agent-data:
+    driver: local