chore: upgrade PostgreSQL to v18 and restructure compose.yaml

compose.yaml

@@ -1,24 +1,22 @@
 services:
   app:
     build: .
+    depends_on:
+      db:
+        condition: service_healthy
     ports:
       - '3000:3000'
     environment:
       DATABASE_URL: postgres://postgres:postgres@db:5432/postgres
-    depends_on:
-      db:
-        condition: service_healthy
 
   db:
-    image: postgres:17-alpine
+    image: postgres:18
-    # ports:
+    volumes:
-    #   - '5432:5432'
+      - pgdata:/var/lib/postgresql/data
     environment:
       POSTGRES_USER: postgres
       POSTGRES_PASSWORD: postgres
       POSTGRES_DB: postgres
-    volumes:
-      - pgdata:/var/lib/postgresql/data
     healthcheck:
       test: [ 'CMD', 'pg_isready', '-U', 'postgres' ]
       interval: 5s