feat: 代理商资金可见性重构（agent-fund-visibility）

- 将 GET /shops/commission-summary 重命名为 GET /shops/fund-summary，
  响应新增 main_balance、main_frozen_balance 两个预充值钱包字段
- 新增 GET /shops/:id/main-wallet/transactions 预充值钱包流水接口
- 将佣金统计、每日统计、发起提现从 /my/ 路径迁移至 /shops/:id/ 路径：
  GET /shops/:id/commission-stats
  GET /shops/:id/commission-daily-stats
  POST /shops/:id/withdrawal-requests
- 删除 MyCommissionService、MyCommissionHandler 及全部 /my/ 路由
- 补齐 ListShopWithdrawalRequests、ListShopCommissionRecords 的
  CanManageShop 越权校验（安全修复）
- 提现接口增加严格权限：仅代理账号本人可为自己店铺发起提现

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/model/dto/commission.go

@@ -60,14 +60,14 @@ type DailyCommissionStatsResponse struct {
 
 // CommissionStatsRequest 佣金统计请求
 type CommissionStatsRequest struct {
-	ShopID    *uint   `json:"shop_id" query:"shop_id" validate:"omitempty" description:"店铺ID"`
+	ShopID    uint    `json:"-" path:"shop_id" description:"店铺ID" required:"true"`
 	StartTime *string `json:"start_time" query:"start_time" validate:"omitempty" description:"开始时间"`
 	EndTime   *string `json:"end_time" query:"end_time" validate:"omitempty" description:"结束时间"`
 }
 
 // DailyCommissionStatsRequest 每日佣金统计请求
 type DailyCommissionStatsRequest struct {
-	ShopID    *uint   `json:"shop_id" query:"shop_id" validate:"omitempty" description:"店铺ID"`
+	ShopID    uint    `json:"-" path:"shop_id" description:"店铺ID" required:"true"`
 	StartDate *string `json:"start_date" query:"start_date" validate:"omitempty" description:"开始日期（YYYY-MM-DD）"`
 	EndDate   *string `json:"end_date" query:"end_date" validate:"omitempty" description:"结束日期（YYYY-MM-DD）"`
 	Days      *int    `json:"days" query:"days" validate:"omitempty,min=1,max=365" minimum:"1" maximum:"365" description:"查询天数（默认30天）"`