合并 main 分支并融合订单列表最小化与 SQL 治理

- Auth/权限中间件取 main 演进版（错误细分、token 来源），保留 dev 的用户 cookie 与登出撤销语义
- 后台订单列表：融合 main 的首页免 COUNT 优化与关键词索引路由，保留 dev 的最小化 AdminOrderListItemDTO（结账明细仍由详情接口返回，同步调整对应集成测试）
- 保留 dev 的 token_version 冻结/解冻递增与 main 的状态变化判断及通知
- 前端：保留 dev 登出接口与 main 的 fetchMe silent 参数、SSE 登录跳转；后台订单表按 dev 最小化 DTO 移除号主到手列

backend/internal/modules/order/presenter.go

@@ -108,6 +108,8 @@ func (row orderRow) toAdminDTO() OrderDTO {
 		GrowthPointsAwarded:         row.GrowthPointsAwarded,
 		GrowthPointsAwardedAt:       row.GrowthPointsAwardedAt,
 		AccountSnapshot:             row.AccountSnapshot,
+		AccountSource:               effectiveAccountSource(row.RentalOrder),
+		SourceChannel:               row.SourceChannel,
 		Status:                      row.Status,
 		HandoffStatus:               row.HandoffStatus,
 		HandoffMode:                 effectiveHandoffMode(row.RentalOrder),
@@ -132,6 +134,13 @@ func (row orderRow) toAdminDTO() OrderDTO {
 	}
 }
 
+func effectiveAccountSource(order model.RentalOrder) string {
+	if order.AccountSource != "" {
+		return order.AccountSource
+	}
+	return "internal"
+}
+
 func (row orderRow) toDTOForUser(userID uint64) OrderDTO {
 	dto := row.toAdminDTO()
 	dto.AdminActions = nil
@@ -147,6 +156,9 @@ func (row orderRow) toDTOForUser(userID uint64) OrderDTO {
 	dto.OfflineSettlementRemark = ""
 	dto.OfflineSettledBy = nil
 	dto.OfflineSettledAt = nil
+	// 外部来源渠道属于后台经营信息，仅在管理员订单详情展示。
+	dto.AccountSource = ""
+	dto.SourceChannel = ""
 	applyOrderPriceView(&dto, row.RentalOrder, userID)
 	return dto
 }
@@ -335,7 +347,7 @@ func refreshCheckoutSettlementDTO(dto *CheckoutDTO, order model.RentalOrder, che
 	if checkout.Status != checkoutStatusSubmitted && checkout.Status != checkoutStatusCountered {
 		return
 	}
-	settlement := calculateCheckoutSettlement(order, checkout.ConsumableAmountCent, checkout.CoinConsumedM, checkout.DepositDeductAmountCent)
+	settlement := calculateCheckoutSettlement(order, checkout.ConsumableAmountCent, checkout.CoinConsumedM, effectiveCheckoutDepositDeductCent(checkout))
 	rent := settlement.ActualRentAmountCent
 	ownerRent := settlement.OwnerRentIncomeCent
 	platform := settlement.PlatformFeeCent