fix: 更换 PostgreSQL 镜像源为轩辕镜像，修复阿里云镜像拉取失败

docker-compose.yml

@@ -29,8 +29,8 @@ services:
     restart: unless-stopped
 
   postgres:
-    # 阿里云镜像，避免从 Docker Hub 拉取超时
+    # 轩辕镜像加速，避免 Docker Hub 拉取超时
-    image: registry.cn-hangzhou.aliyuncs.com/library/postgres:15-alpine
+    image: docker.xuanyuan.me/library/postgres:15-alpine
     container_name: camtalk-postgres
     environment:
       POSTGRES_USER: camtalk