feat: 增加共享 Agent Browser 调试能力

需求：在 AI 编程会话中让用户与 Agent 共享同一浏览器页面，并查看控制台与网络信息。

实现：新增沙箱浏览器内核、Host API/渲染器面板、OpenCode 工具接入及安全边界测试。

electron/agent-browser/adapter.ts

@@ -0,0 +1,52 @@
+import type { AgentBrowserBounds } from '../../shared/agent-browser';
+
+export type PortListener = (...args: unknown[]) => void;
+
+export interface AgentBrowserDebuggerPort {
+  attach(protocolVersion: string): void;
+  detach(): void;
+  isAttached(): boolean;
+  sendCommand(
+    method: string,
+    params?: Record<string, unknown>,
+    sessionRef?: string,
+  ): Promise<unknown>;
+  on(event: 'message' | 'detach', listener: PortListener): void;
+  removeListener(event: 'message' | 'detach', listener: PortListener): void;
+}
+
+export interface AgentBrowserNavigationPort {
+  canGoBack(): boolean;
+  canGoForward(): boolean;
+  goBack(): void;
+  goForward(): void;
+  clear(): void;
+}
+
+export interface AgentBrowserWebContentsPort {
+  readonly debugger: AgentBrowserDebuggerPort;
+  readonly navigationHistory: AgentBrowserNavigationPort;
+  loadURL(url: string): Promise<void>;
+  getURL(): string;
+  getTitle(): string;
+  isDestroyed(): boolean;
+  isDevToolsOpened(): boolean;
+  reload(): void;
+  denyWindowOpen(): void;
+  on(event: string, listener: PortListener): void;
+  removeListener(event: string, listener: PortListener): void;
+}
+
+export interface AgentBrowserViewPort {
+  readonly webContents: AgentBrowserWebContentsPort;
+  setBounds(bounds: AgentBrowserBounds): void;
+  setVisible(visible: boolean): void;
+}
+
+export interface AgentBrowserAdapter {
+  createView(partition: string): AgentBrowserViewPort;
+  mount(view: AgentBrowserViewPort): void;
+  unmount(view: AgentBrowserViewPort): void;
+  destroy(view: AgentBrowserViewPort): void;
+  resetPartition(partition: string): Promise<void>;
+}