feat(category): update list filter category

internal/repository/category_repository.go

@@ -63,6 +63,21 @@ func (r *CategoryRepositoryImpl) Delete(ctx context.Context, id uuid.UUID) error
 	return r.db.WithContext(ctx).Delete(&entities.Category{}, "id = ?", id).Error
 }
 
+// applyCategoryTypeFilter narrows the query by position in the category tree.
+//   - "parent": top level categories only (no parent of their own)
+//   - "child":  leaf categories — sub categories plus top level categories that
+//     have no sub categories, i.e. everything a product can be assigned to
+func applyCategoryTypeFilter(query *gorm.DB, value interface{}) *gorm.DB {
+	switch value {
+	case "parent":
+		return query.Where("parent_id IS NULL")
+	case "child":
+		return query.Where("NOT EXISTS (SELECT 1 FROM categories AS sub WHERE sub.parent_id = categories.id)")
+	default:
+		return query
+	}
+}
+
 func (r *CategoryRepositoryImpl) List(ctx context.Context, filters map[string]interface{}, limit, offset int) ([]*entities.Category, int64, error) {
 	var categories []*entities.Category
 	var total int64
@@ -77,6 +92,8 @@ func (r *CategoryRepositoryImpl) List(ctx context.Context, filters map[string]in
 		case "outlet_id":
 			// Include outlet-specific categories AND global categories (outlet_id IS NULL)
 			query = query.Where("outlet_id = ? OR outlet_id IS NULL", value)
+		case "type":
+			query = applyCategoryTypeFilter(query, value)
 		default:
 			query = query.Where(key+" = ?", value)
 		}
@@ -101,6 +118,8 @@ func (r *CategoryRepositoryImpl) Count(ctx context.Context, filters map[string]i
 			query = query.Where("name ILIKE ? OR description ILIKE ?", searchValue, searchValue)
 		case "outlet_id":
 			query = query.Where("outlet_id = ? OR outlet_id IS NULL", value)
+		case "type":
+			query = applyCategoryTypeFilter(query, value)
 		default:
 			query = query.Where(key+" = ?", value)
 		}