全局重命名：kefu_sys / kefu-sys 改为 kefu_cloud / kefu-cloud

- Go module 与全部 import 路径
- 数据库默认库名、Docker 服务/卷命名与部署文档

server/internal/middleware/auth.go

@@ -10,7 +10,7 @@ import (
 
 	"github.com/gin-gonic/gin"
 	"github.com/golang-jwt/jwt/v5"
-	"kefu-sys/server/internal/model"
+	"kefu-cloud/server/internal/model"
 )
 
 var jwtSecret []byte