fix(distribution): 修正商品归属回填、禁止全站灌货并拒绝无效站点头

用货架写入时间与上传来源回滚误标产地，不再依赖绝对时间戳；同步仅收本站上传与显式勾选。

backend/internal/modules/distribution/repository.go

@@ -41,8 +41,12 @@ var (
 	ErrDuplicateSiteCodeOrDomain = errors.New("distribution site code or domain already exists")
 	ErrDuplicateUsername         = errors.New("username already exists")
 	ErrLiveMoneyMovementFrozen   = errors.New("distribution settlement and withdrawal frozen until split rules are verified")
+	ErrTooManySyncListings       = errors.New("too many listings to sync")
+	ErrSyncListingNotFound       = errors.New("sync listing not found")
 )
 
+const maxSyncListingIDs = 200
+
 func liveMoneyMovementEnabled() bool {
 	env := strings.ToLower(strings.TrimSpace(os.Getenv("APP_ENV")))
 	return env != "production" && env != "prod"
@@ -507,7 +511,26 @@ func (r *Repository) UpdateAccountDisplay(ctx context.Context, adminID, id uint6
 	return item, nil
 }
 
-func (r *Repository) SyncSiteAccounts(ctx context.Context, adminID, siteID uint64) (*SyncSiteAccountsResult, error) {
+func uniquePositiveIDs(ids []uint64) []uint64 {
+	if len(ids) == 0 {
+		return nil
+	}
+	seen := make(map[uint64]struct{}, len(ids))
+	out := make([]uint64, 0, len(ids))
+	for _, id := range ids {
+		if id == 0 {
+			continue
+		}
+		if _, ok := seen[id]; ok {
+			continue
+		}
+		seen[id] = struct{}{}
+		out = append(out, id)
+	}
+	return out
+}
+
+func (r *Repository) SyncSiteAccounts(ctx context.Context, adminID, siteID uint64, listingIDs []uint64) (*SyncSiteAccountsResult, error) {
 	if r.db == nil {
 		return nil, ErrDependencyUnavailable
 	}
@@ -522,14 +545,40 @@ func (r *Repository) SyncSiteAccounts(ctx context.Context, adminID, siteID uint6
 		return nil, err
 	}
 
-	var activeListings []model.RentalListing
+	selectedIDs := uniquePositiveIDs(listingIDs)
+	if len(selectedIDs) > maxSyncListingIDs {
+		return nil, ErrTooManySyncListings
+	}
+
+	var candidates []model.RentalListing
 	if err := r.db.WithContext(ctx).
-		Where("status = ? AND review_status = ?", "published", "approved").
+		Where("distribution_site_id = ? AND status = ? AND review_status = ?", siteID, "published", "approved").
 		Order("id ASC").
-		Find(&activeListings).Error; err != nil {
+		Find(&candidates).Error; err != nil {
 		return nil, err
 	}
 
+	if len(selectedIDs) > 0 {
+		var selected []model.RentalListing
+		if err := r.db.WithContext(ctx).Where("id IN ?", selectedIDs).Find(&selected).Error; err != nil {
+			return nil, err
+		}
+		if len(selected) != len(selectedIDs) {
+			return nil, ErrSyncListingNotFound
+		}
+		seenListing := make(map[uint64]bool, len(candidates)+len(selected))
+		for _, l := range candidates {
+			seenListing[l.ID] = true
+		}
+		for _, l := range selected {
+			if seenListing[l.ID] {
+				continue
+			}
+			seenListing[l.ID] = true
+			candidates = append(candidates, l)
+		}
+	}
+
 	var existingAccounts []model.DistributionSiteAccount
 	if err := r.db.WithContext(ctx).
 		Where("site_id = ?", siteID).
@@ -546,7 +595,7 @@ func (r *Repository) SyncSiteAccounts(ctx context.Context, adminID, siteID uint6
 	seenAccount := make(map[uint64]bool)
 	var skippedCount int64
 
-	for _, l := range activeListings {
+	for _, l := range candidates {
 		if seenAccount[l.AccountID] {
 			continue
 		}
@@ -577,7 +626,7 @@ func (r *Repository) SyncSiteAccounts(ctx context.Context, adminID, siteID uint6
 	return &SyncSiteAccountsResult{
 		SyncedCount:  int64(len(toInsert)),
 		SkippedCount: skippedCount,
-		TotalActive:  int64(len(activeListings)),
+		TotalActive:  int64(len(candidates)),
 	}, nil
 }
 
@@ -1096,34 +1145,6 @@ func (r *Repository) OnboardSite(ctx context.Context, req OnboardSiteRequest) (*
 			return err
 		}
 
-		if displayEnabled {
-			var activeListings []model.RentalListing
-			if err := tx.Where("status = ? AND review_status = ?", "published", "approved").Order("id ASC").Find(&activeListings).Error; err != nil {
-				return err
-			}
-			if len(activeListings) > 0 {
-				siteAccounts := make([]model.DistributionSiteAccount, 0, len(activeListings))
-				seenAccount := make(map[uint64]bool)
-				for _, l := range activeListings {
-					if seenAccount[l.AccountID] {
-						continue
-					}
-					seenAccount[l.AccountID] = true
-					siteAccounts = append(siteAccounts, model.DistributionSiteAccount{
-						SiteID:        site.ID,
-						AccountID:     l.AccountID,
-						ListingID:     l.ID,
-						DisplayStatus: "enabled",
-					})
-				}
-				if len(siteAccounts) > 0 {
-					if err := tx.Create(&siteAccounts).Error; err != nil {
-						return err
-					}
-				}
-			}
-		}
-
 		resp = OnboardSiteResponse{
 			Site: siteDTO(site),
 			Rule: ruleDTO(rule),