feat: add pgadmin to deployment

docker-compose.yaml

@@ -76,6 +76,25 @@ services:
       dagster-usercode:
         condition: service_healthy
 
+  # pgAdmin web UI
+  pgadmin:
+    image: dpage/pgadmin4:latest
+    container_name: pgadmin
+    restart: unless-stopped
+    env_file: .env
+    environment:
+      PGADMIN_DEFAULT_EMAIL: ${PGADMIN_EMAIL}
+      PGADMIN_DEFAULT_PASSWORD: ${PGADMIN_PASSWORD}
+    volumes:
+      - pgadmin-data:/var/lib/pgadmin
+      - ./pgadmin/servers.json:/pgadmin4/servers.json:ro
+    ports:
+      - "5050:80"
+    depends_on:
+      postgres:
+        condition: service_healthy
+
 volumes:
   postgres-data:
   dbt-target:
+  pgadmin-data: