refactor(vscode-ide-companion): 重构 WebViewProvider 初始化逻辑

- 抽离初始化代理连接逻辑到单独的方法中
- 优化面板恢复时的代理连接流程
- 移除 EmptyState 组件中的信息横幅
- 在 App 组件中添加可关闭的信息横幅
- 调整输入表单样式，移除冗余样式

packages/vscode-ide-companion/src/webview/App.tsx

@@ -526,7 +526,7 @@ export const App: React.FC = () => {
                 role="textbox"
                 aria-label="Message input"
                 aria-multiline="true"
-                data-placeholder="Ask Claude to edit…"
+                data-placeholder="Ask qwen to edit…"
                 onInput={(e) => {
                   const target = e.target as HTMLDivElement;
                   setInputText(target.textContent || '');
@@ -544,7 +544,7 @@ export const App: React.FC = () => {
               <button
                 type="button"
                 className="action-button edit-mode-button"
-                title="Claude will ask before each edit. Click to switch modes."
+                title="Qwen will ask before each edit. Click to switch modes."
               >
                 <svg
                   xmlns="http://www.w3.org/2000/svg"