feat(distribution): 通道费改主站承担，并按冷却期自动释放结算

利润不再扣支付通道费；站点可配置结算冷却期，到期自动入账，已释放后退款从收款站钱包回冲。同时修复当日自动批次无法追加、三方回冲打错钱包，以及测试库自增重置被 MySQL 统计缓存跳过的问题。

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/internal/modules/distribution/repository_test.go

@@ -23,6 +23,7 @@ func distributionTestDB(t *testing.T) *gorm.DB {
 		&model.DistributionSettlementBatch{}, &model.DistributionSettlementItem{},
 		&model.RentalListing{}, &model.GameAccount{}, &model.User{},
 		&model.WalletAccount{}, &model.WalletLedger{}, &model.WithdrawalRequest{},
+		&model.Dispute{},
 	); err != nil {
 		t.Fatal(err)
 	}
@@ -984,3 +985,93 @@ func TestLiveMoneyMovementFrozenInProduction(t *testing.T) {
 		t.Fatalf("withdraw err = %v", err)
 	}
 }
+
+func TestUpdateSiteRewritesPendingReleaseAt(t *testing.T) {
+	db := distributionTestDB(t)
+	repo := NewRepository(db)
+	now := time.Now()
+	site := mustCreateDistSite(t, db, "hold_upd", "冷却回写站", "holdupd.dist.com")
+	if err := db.Model(&site).Update("settlement_hold_days", 7).Error; err != nil {
+		t.Fatal(err)
+	}
+	rule := mustCreateActiveRule(t, db, site.ID, ModeTwoPartyDistributorReceive, now)
+	settledAt := now.Add(-time.Hour).Truncate(time.Second)
+	order := model.RentalOrder{
+		OrderNo: "ORD-HOLD-UPD", ListingID: 1, AccountID: 2, OwnerID: 3, RenterID: 4,
+		Status: "completed", RentAmountCent: 10000, OwnerRentAmountCent: 6000,
+		DistributionSiteID: &site.ID, DistributionRuleVersionID: &rule.ID,
+		SettledAt: &settledAt,
+	}
+	if err := db.Create(&order).Error; err != nil {
+		t.Fatal(err)
+	}
+	oldRelease := settledAt.AddDate(0, 0, 7)
+	if err := db.Create(&model.DistributionOrderFinancial{
+		OrderID: order.ID, SiteID: site.ID, RuleVersionID: rule.ID,
+		GrossPaidAmountCent: 10000, SettlementStatus: "pending", ReleaseAt: &oldRelease,
+	}).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	holdDays := 0
+	if _, err := repo.UpdateSite(t.Context(), 0, site.ID, UpdateSiteRequest{SettlementHoldDays: &holdDays}); err != nil {
+		t.Fatal(err)
+	}
+	var financial model.DistributionOrderFinancial
+	if err := db.Where("order_id = ?", order.ID).First(&financial).Error; err != nil {
+		t.Fatal(err)
+	}
+	if financial.ReleaseAt == nil || !financial.ReleaseAt.Equal(settledAt) {
+		t.Fatalf("release_at = %v, want %v after hold days set to 0", financial.ReleaseAt, settledAt)
+	}
+}
+
+func TestGetSiteWalletPendingReleaseExcludesOpenDispute(t *testing.T) {
+	db := distributionTestDB(t)
+	repo := NewRepository(db)
+	now := time.Now()
+	site := mustCreateDistSite(t, db, "pend_dsp", "待释放纠纷站", "penddsp.dist.com")
+	rule := mustCreateActiveRule(t, db, site.ID, ModeTwoPartyDistributorReceive, now)
+	past := now.Add(-time.Minute)
+	order := model.RentalOrder{
+		OrderNo: "ORD-PEND-DSP", ListingID: 1, AccountID: 2, OwnerID: 3, RenterID: 4,
+		Status: "completed", RentAmountCent: 10000, OwnerRentAmountCent: 6000, RefundStatus: "none",
+		DistributionSiteID: &site.ID, DistributionRuleVersionID: &rule.ID,
+	}
+	if err := db.Create(&order).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := db.Create(&model.DistributionOrderFinancial{
+		OrderID: order.ID, SiteID: site.ID, RuleVersionID: rule.ID,
+		GrossPaidAmountCent: 10000, SettlementStatus: "pending", ReleaseAt: &past,
+	}).Error; err != nil {
+		t.Fatal(err)
+	}
+	if err := db.Create(&model.DistributionOrderParty{
+		OrderID: order.ID, SiteID: site.ID, PartyRole: "distributor_receive",
+		PartyType: PartyTypeSite, PartyID: site.ID, IncomeAmountCent: 1400,
+	}).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	walletDTO, err := repo.GetSiteWallet(t.Context(), 0, site.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if walletDTO.PendingReleaseCent != 1400 {
+		t.Fatalf("pending release = %d, want 1400", walletDTO.PendingReleaseCent)
+	}
+
+	if err := db.Create(&model.Dispute{
+		OrderID: order.ID, InitiatorID: 4, TargetUserID: 3, Type: "cannot_login", Status: "open",
+	}).Error; err != nil {
+		t.Fatal(err)
+	}
+	walletDTO, err = repo.GetSiteWallet(t.Context(), 0, site.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if walletDTO.PendingReleaseCent != 0 {
+		t.Fatalf("pending release with open dispute = %d, want 0", walletDTO.PendingReleaseCent)
+	}
+}