refactor: 重构 AgentScope 运行时模块并优化前端附件展示

apps/lib/features/chat/data/services/ag_ui_service.dart

@@ -249,7 +249,6 @@ class AgUiService {
     final runId = _nextId(_runIdPrefix);
 
     final contentBlocks = <Map<String, dynamic>>[];
-    final attachmentMetadata = <Map<String, dynamic>>[];
 
     if (content.isNotEmpty) {
       contentBlocks.add({'type': 'text', 'text': content});
@@ -266,11 +265,6 @@ class AgUiService {
           'mimeType': attachment['mimeType'],
           'url': attachment['url'],
         });
-        attachmentMetadata.add({
-          'bucket': attachment['bucket'],
-          'path': attachment['path'],
-          'mimeType': attachment['mimeType'],
-        });
       }
     }
 
@@ -293,9 +287,7 @@ class AgUiService {
       ],
       'tools': _buildTools(),
       'context': <Map<String, dynamic>>[],
-      'forwardedProps': {
-        if (attachmentMetadata.isNotEmpty) 'attachments': attachmentMetadata,
-      },
+      'forwardedProps': <String, dynamic>{},
     };
   }