功能：优化账号分层与管理员初始化

backend/internal/router/router.go

@@ -193,8 +193,10 @@ func Setup(h *Handlers) *gin.Engine {
 			admin.Use(middleware.RequireRole(model.RoleAdmin))
 			{
 				admin.GET("/users", h.User.List)
+				admin.GET("/platform/members", h.User.ListMerchantMembers)
 				admin.POST("/users", h.User.Create)
 				admin.PATCH("/users/:id/status", h.User.UpdateStatus)
+				admin.PATCH("/users/:id/role", h.User.UpdateRole)
 				admin.DELETE("/users/:id", h.User.Delete)
 				admin.GET("/platform/merchants", h.Merchant.ListPlatformMerchants)
 				admin.POST("/platform/merchants", h.Merchant.CreateMerchant)