fix: rename postgres service to postgresql and add healthcheck configuration

compose.yml

@@ -1,6 +1,6 @@
 ---
 services:
-  postgres:
+  postgresql:
     image: postgres:16-alpine
     restart: unless-stopped
     volumes:
@@ -11,11 +11,20 @@ services:
       POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-ivatar_secure_password}
     networks:
       - ivatar-network
+    healthcheck:
+      test:
+        - CMD-SHELL
+        - pg_isready -U ivatar -d ivatar
+      interval: 10s
+      timeout: 5s
+      retries: 5
+      start_period: 30s
   ivatar:
     image: gitea.purpleraft.com/ryan/ivatar-docker:latest
     restart: unless-stopped
     depends_on:
-      - postgres
+      postgresql:
+        condition: service_healthy
     ports:
       - '8080:8080'
     volumes:
@@ -27,8 +36,6 @@ services:
       POSTGRESQL_DATABASE: ivatar
       POSTGRESQL_USER: ivatar
       POSTGRESQL_PASSWORD: ${POSTGRES_PASSWORD:-ivatar_secure_password}
-      POSTGRESQL_HOST: postgres
-      POSTGRESQL_PORT: 5432
       EMAIL_BACKEND: ${EMAIL_BACKEND:-django.core.mail.backends.console.EmailBackend}
       SERVER_EMAIL: ${SERVER_EMAIL:-ivatar@your-domain.com}
       DEFAULT_FROM_EMAIL: ${DEFAULT_FROM_EMAIL:-ivatar@your-domain.com}