FIX: remove duplicate identifier_columns declaration in TableColumns DTO

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/modules/inputs/dtos/input.model.ts

@@ -14,6 +14,11 @@ export class TableColumns {
   @ApiPropertyOptional({ type: [Column] })
   references: Column[];
   @ApiProperty()
+  destination: Record<'raw' | 'qualify', {
+    table_name: string;
+    table_schema: string;
+  }> | null;
+  @ApiProperty()
   type: string;
   @ApiPropertyOptional({ type: [String] })
   identifier_columns?: string[];