feat(dc): Complete Tool C Day 5 - AI Chat + Ant Design X Integration

Summary:
- Upgrade to Ant Design 6.0.1 + install Ant Design X (2.1.0) + X SDK (2.1.0)
- Develop frontend common capability layer: Chat component library (~968 lines)
  * ChatContainer.tsx - Core container component
  * MessageRenderer.tsx - Message renderer
  * CodeBlockRenderer.tsx - Code block renderer with syntax highlighting
  * Complete TypeScript types and documentation
- Integrate ChatContainer into Tool C
- Fix 7 critical UI issues:
  * AG Grid module registration error
  * UI refinement (borders, shadows, gradients)
  * Add AI welcome message
  * Auto-clear input field after sending
  * Remove page scrollbars
  * Manual code execution (not auto-run)
  * Support simple Q&A (new /ai/chat API)
- Complete end-to-end testing
- Update all documentation (4 status docs + 6 dev logs)

Technical Stack:
- Frontend: React 19 + Ant Design 6.0 + Ant Design X 2.1
- Components: Bubble, Sender from @ant-design/x
- Total code: ~5418 lines

Status: Tool C MVP completed, production ready

frontend-v2/src/shared/components/Chat/CodeBlockRenderer.tsx

@@ -0,0 +1,70 @@
+/**
+ * CodeBlockRenderer - 代码块渲染器
+ * 
+ * Tool C 专用：显示 AI 生成的代码，支持语法高亮和执行
+ */
+
+import React, { useEffect } from 'react';
+import { Button } from 'antd';
+import { PlayCircleOutlined, LoadingOutlined } from '@ant-design/icons';
+import Prism from 'prismjs';
+import 'prismjs/themes/prism-tomorrow.css';
+import 'prismjs/components/prism-python';
+import type { CodeBlockRendererProps } from './types';
+
+export const CodeBlockRenderer: React.FC<CodeBlockRendererProps> = ({
+  code,
+  language = 'python',
+  onExecute,
+  isExecuting = false,
+  executionResult,
+}) => {
+  // 语法高亮
+  useEffect(() => {
+    Prism.highlightAll();
+  }, [code]);
+
+  const handleExecute = () => {
+    if (onExecute && !isExecuting) {
+      onExecute(code);
+    }
+  };
+
+  return (
+    <div className="code-block-container">
+      <div className="code-block-header">
+        <span className="code-language">{language}</span>
+        {onExecute && (
+          <Button
+            type="primary"
+            size="small"
+            icon={isExecuting ? <LoadingOutlined /> : <PlayCircleOutlined />}
+            onClick={handleExecute}
+            disabled={isExecuting}
+            className="execute-button"
+          >
+            {isExecuting ? '执行中...' : '运行代码'}
+          </Button>
+        )}
+      </div>
+
+      <pre className="code-block">
+        <code className={`language-${language}`}>
+          {code}
+        </code>
+      </pre>
+
+      {executionResult && (
+        <div className={`execution-result ${executionResult.success ? 'success' : 'error'}`}>
+          {executionResult.success ? (
+            <span>✅ 执行成功</span>
+          ) : (
+            <span>❌ {executionResult.message || '执行失败'}</span>
+          )}
+        </div>
+      )}
+    </div>
+  );
+};
+
+export default CodeBlockRenderer;