Reapply "feat(controller): 完善基础控制器及默认页面渲染"

This reverts commit 1a3bd1a6b3.

controller/admin/userController.go

@@ -3,10 +3,11 @@ package admin
 import "github.com/gin-gonic/gin"
 
 type UserController struct {
+	BaseController
 }
 
 func (con UserController) Index(c *gin.Context) {
-	c.String(200, "管理员用户列表")
+	con.Success(c)
 }
 
 func (con UserController) Show(c *gin.Context) {