fix(assets,storyboard): 统一素材库 entity 口径、修复远端空结果遮蔽，补分镜输出契约与解析 (#510)

远端空页只在本地仍有未同步结果或本页全是 entity 时回退，避免把合法空搜索铺成过期缓存。

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

backend/internal/repository/asset_library.go

@@ -28,7 +28,9 @@ type UserAssetFacetRow struct {
 func (r *Repository) UserAssetsPage(userID string, page int, pageSize int, filter UserAssetPageFilter) ([]model.Asset, int64, error) {
 	var assets []model.Asset
 	var total int64
-	query := userAssetFilteredQuery(r.db.Model(&model.Asset{}).Where("user_id = ?", userID), filter, true)
+	// 素材库页面只展示媒体与文本素材；entity 角色卡由项目资产页管理。列表与 facets 必须同口径排除，
+	// 否则 facets 会计入 entity，前端出现“全部计数 30 但列表为空”的矛盾。
+	query := userAssetFilteredQuery(r.db.Model(&model.Asset{}).Where("user_id = ? AND kind <> ?", userID, "entity"), filter, true)
 	if err := query.Count(&total).Error; err != nil {
 		return nil, 0, err
 	}
@@ -38,7 +40,7 @@ func (r *Repository) UserAssetsPage(userID string, page int, pageSize int, filte
 
 func (r *Repository) UserAssetFacets(userID string, status string) ([]UserAssetFacetRow, []UserAssetFacetRow, []UserAssetFacetRow, error) {
 	base := func() *gorm.DB {
-		return userAssetFilteredQuery(r.db.Model(&model.Asset{}).Where("user_id = ?", userID), UserAssetPageFilter{Status: status}, false)
+		return userAssetFilteredQuery(r.db.Model(&model.Asset{}).Where("user_id = ? AND kind <> ?", userID, "entity"), UserAssetPageFilter{Status: status}, false)
 	}
 	var kindRows []UserAssetFacetRow
 	if err := base().Select("kind AS key, COUNT(*) AS count").Group("kind").Scan(&kindRows).Error; err != nil {