fix: Gitea Traefik routing and connection pool optimization

- Remove middleware reference from Gitea Traefik labels (caused routing issues)
- Optimize Gitea connection pool settings (MAX_IDLE_CONNS=30, authentication_timeout=180s)
- Add explicit service reference in Traefik labels
- Fix intermittent 504 timeouts by improving PostgreSQL connection handling

Fixes Gitea unreachability via git.michaelschiemer.de

deployment/stacks/postgresql-production/docker-compose.yml

@@ -0,0 +1,72 @@
+services:
+  # PostgreSQL Production Database
+  postgres-production:
+    image: postgres:16-alpine
+    container_name: postgres-production
+    restart: unless-stopped
+    networks:
+      - postgres-production-internal
+    environment:
+      - TZ=Europe/Berlin
+      - POSTGRES_DB=${POSTGRES_DB:-michaelschiemer}
+      - POSTGRES_USER=${POSTGRES_USER:-postgres}
+      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
+      - PGDATA=/var/lib/postgresql/data/pgdata
+    volumes:
+      - postgres-production-data:/var/lib/postgresql/data
+      - ./conf.d:/etc/postgresql/conf.d:ro
+      - ./backups:/backups
+      - /etc/timezone:/etc/timezone:ro
+      - /etc/localtime:/etc/localtime:ro
+    command:
+      - postgres
+      - -c
+      - config_file=/etc/postgresql/conf.d/postgresql.conf
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-michaelschiemer}"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 40s
+    shm_size: 256mb
+    deploy:
+      resources:
+        limits:
+          memory: 2G
+        reservations:
+          memory: 512M
+
+  # Automated Backup Service for Production
+  postgres-production-backup:
+    image: postgres:16-alpine
+    container_name: postgres-production-backup
+    restart: unless-stopped
+    networks:
+      - postgres-production-internal
+    environment:
+      - TZ=Europe/Berlin
+      - POSTGRES_HOST=postgres-production
+      - POSTGRES_DB=${POSTGRES_DB:-michaelschiemer}
+      - POSTGRES_USER=${POSTGRES_USER:-postgres}
+      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
+      - BACKUP_RETENTION_DAYS=${BACKUP_RETENTION_DAYS:-7}
+      - BACKUP_SCHEDULE=${BACKUP_SCHEDULE:-0 2 * * *}
+    volumes:
+      - ./backups:/backups
+      - ./scripts:/scripts:ro
+      - /etc/timezone:/etc/timezone:ro
+      - /etc/localtime:/etc/localtime:ro
+    entrypoint: ["/scripts/backup-entrypoint.sh"]
+    depends_on:
+      postgres-production:
+        condition: service_healthy
+
+volumes:
+  postgres-production-data:
+    name: postgres-production-data
+
+networks:
+  postgres-production-internal:
+    name: postgres-production-internal
+    driver: bridge
+