✨ feat(topup): Admin-wide topup listing and route reorganization

Allow administrators to view all platform topup orders and streamline admin-only routes.

Frontend
- TopupHistoryModal: dynamically switch endpoint by role
  - Admin → GET /api/user/topup (all orders)
  - Non-admin → GET /api/user/topup/self (own orders)
- Use shared utils `isAdmin()`; keep logic centralized and DRY
- Minor UI: set admin action button theme to outline for clarity

Backend
- model/topup.go: add GetAllTopUps(pageInfo) with pagination (ordered by id desc)
- controller/topup.go: add GetAllTopUps handler returning PageInfo response
- router/api-router.go:
  - Add admin route GET /api/user/topup (AdminAuth)
  - Move POST /api/user/topup/complete to adminRoute (keeps path stable, consolidates admin endpoints)

Security/Behavior
- Admin-only endpoints now reside under the admin route group with AdminAuth
- No behavior change for regular users; no schema changes

Affected files
- model/topup.go
- controller/topup.go
- router/api-router.go
- web/src/components/topup/modals/TopupHistoryModal.jsx

controller/topup.go

@@ -330,6 +330,21 @@ func GetUserTopUps(c *gin.Context) {
 	common.ApiSuccess(c, pageInfo)
 }
 
+// GetAllTopUps 管理员获取全平台充值记录
+func GetAllTopUps(c *gin.Context) {
+	pageInfo := common.GetPageQuery(c)
+
+	topups, total, err := model.GetAllTopUps(pageInfo)
+	if err != nil {
+		common.ApiError(c, err)
+		return
+	}
+
+	pageInfo.SetTotal(int(total))
+	pageInfo.SetItems(topups)
+	common.ApiSuccess(c, pageInfo)
+}
+
 type AdminCompleteTopupRequest struct {
 	TradeNo string `json:"trade_no"`
 }