cockpit: file upload support — read files, inject to LLM, emit file widgets

- Parse file_paths from request, read file contents (UTF-8, max 8000 chars)
- File content appended to LLM message as 【附件文件内容】
- File widget streamed to frontend: 📎 filename (size) + hidden content preview
- Frontend script: click .file-name → toggle .file-content visibility
- File paths saved in pipeline_conversations.attachments

wwwroot/api/cockpit_chat.dspy

@@ -310,12 +310,39 @@ _tool_names = {
 def _tool_label(tool):
     return _tool_names.get(tool, tool)
 
+def _widget_file(filename, content_preview, file_size=0):
+    """Bricks widget: file attachment with expandable content preview."""
+    size_str = f" ({file_size} bytes)" if file_size else ""
+    return {
+        "widgettype": "VBox",
+        "options": {
+            "css": "agent-file",
+            "style": {"border": "1px solid #e2e8f0", "borderRadius": "8px", "padding": "8px 12px", "margin": "4px 0"}
+        },
+        "subwidgets": [
+            {"widgettype": "HBox", "subwidgets": [
+                {"widgettype": "Text", "options": {"text": f"📎 {filename}{size_str}", "css": "file-name",
+                   "style": {"color": "#2563eb", "cursor": "pointer", "fontSize": "13px", "fontWeight": "bold"}}}
+            ]},
+            {"widgettype": "Text", "options": {"text": content_preview or "(空文件)", "css": "file-content",
+               "style": {"display": "none", "whiteSpace": "pre-wrap", "fontSize": "12px", "color": "#475569",
+                         "background": "#f8fafc", "borderRadius": "4px", "padding": "8px", "marginTop": "6px",
+                         "maxHeight": "300px", "overflowY": "auto"}}}
+        ]
+    }
+
 
 # ── Streaming Agent Loop ──
 
 if action == 'send_message':
     message_text = (params_kw or {}).get('message_text', '').strip()
     user_model_id = (params_kw or {}).get('model_id', '')
+    file_paths_raw = (params_kw or {}).get('file_paths', '[]')
+    file_paths = []
+    try:
+        file_paths = json.loads(file_paths_raw) if isinstance(file_paths_raw, str) else (file_paths_raw or [])
+    except (json.JSONDecodeError, TypeError):
+        file_paths = []
 
     if not message_text:
         return json.dumps({"error": "message_text is required"}, ensure_ascii=False)
@@ -346,8 +373,29 @@ if action == 'send_message':
             for h in (history or []):
                 msgs.append({"role":'user' if getattr(h,'role','')=='user' else 'assistant',"content":getattr(h,'content','')})
 
-            await sor.C('pipeline_conversations',{'id':getID(),'iteration_id':'','task_id':'','role':'user','content':message_text,'attachments':'[]','msg_type':'text','org_id':org_id,'created_by':uid})
-            msgs.append({"role":"user","content":message_text})
+            await sor.C('pipeline_conversations',{'id':getID(),'iteration_id':'','task_id':'','role':'user','content':message_text,'attachments':json.dumps(file_paths),'msg_type':'text','org_id':org_id,'created_by':uid})
+
+            # 处理上传文件：读取内容、发送文件widget、注入LLM上下文
+            file_contents = []
+            for fp in file_paths:
+                try:
+                    if os.path.isfile(fp):
+                        with open(fp, 'r', encoding='utf-8', errors='replace') as f:
+                            content = f.read()[:8000]
+                        fsize = os.path.getsize(fp)
+                        fname = os.path.basename(fp)
+                        file_contents.append(f"=== 文件: {fname} ===\n{content}")
+                        # 发送文件widget
+                        preview = content[:1000] + ("\n...(截断)" if len(content) > 1000 else "")
+                        yield json.dumps({"type":"widget","widget":_widget_file(fname, preview, fsize)}, ensure_ascii=False) + '\n'
+                except Exception:
+                    pass
+
+            # 把用户消息+文件内容合并为一条LLM消息
+            full_message = message_text
+            if file_contents:
+                full_message = message_text + "\n\n【附件文件内容】\n" + "\n\n".join(file_contents)
+            msgs.append({"role":"user","content":full_message})
 
             agent_reply = ''
             for turn in range(10):