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/opencode/manager.ts

@@ -8,6 +8,7 @@ import {
   type SpawnOptionsWithoutStdio,
 } from 'node:child_process';
 import {
+  ensureBundledAgentBrowserPlugin,
   ensureBundledCourseSkills,
   ensureBundledSuperpowersPlugin,
   getManagedOpencodeConfigDir,
@@ -163,6 +164,7 @@ export interface OpencodeManagerOptions {
   userDataDir?: string;
   bundledSuperpowersDir?: string;
   bundledCourseSkillsDir?: string;
+  bundledAgentBrowserPluginPath?: string;
   pythonRuntime?: PythonRuntime;
   spawn?: SpawnFn;
   configProvider?: ConfigProvider;
@@ -580,6 +582,10 @@ export class OpencodeManager extends EventEmitter {
       managedConfigDir,
       sourceDir: this.options.bundledCourseSkillsDir,
     });
+    ensureBundledAgentBrowserPlugin({
+      managedConfigDir,
+      sourcePath: this.options.bundledAgentBrowserPluginPath,
+    });
     const environment = {
       ...runtimeEnv,
       OPENCODE_CONFIG_DIR: managedConfigDir,