feat: 添加配置面板组件

- 新增 ConfigPanel 组件，支持模型选择、参数调整
- 添加配置 API (getConfig/updateConfig)
- 在 App.tsx 中集成配置按钮和面板

packages/web/src/api/client.ts

@@ -161,3 +161,21 @@ export async function getFileTree(path: string = '.', depth: number = 3): Promis
   const params = new URLSearchParams({ path, depth: String(depth) });
   return request('GET', `/files/tree?${params}`);
 }
+
+// Config
+export interface ServerConfig {
+  model: string;
+  maxTokens: number;
+  temperature: number;
+  workdir: string;
+  allowedPaths: string[];
+  deniedPaths: string[];
+}
+
+export async function getConfig(): Promise<{ success: boolean; data: ServerConfig }> {
+  return request('GET', '/config');
+}
+
+export async function updateConfig(config: Partial<ServerConfig>): Promise<{ success: boolean; data: ServerConfig }> {
+  return request('PATCH', '/config', config);
+}