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/api/routes/opencode.ts

@@ -585,6 +585,24 @@ async function findProjectById(ctx: HostApiContext, projectId: string) {
   return projects.find((project) => project.id === projectId) ?? null;
 }
 
+async function closeAgentBrowserForProject(
+  ctx: HostApiContext,
+  projectPath: string,
+): Promise<void> {
+  try {
+    await ctx.agentBrowser?.close(projectPath);
+  } catch (error) {
+    if (
+      error
+      && typeof error === 'object'
+      && (error as { code?: unknown }).code === 'PROJECT_MISMATCH'
+    ) {
+      return;
+    }
+    throw error;
+  }
+}
+
 type ProjectActivationCheck =
   | { ok: true }
   | { ok: false; status: Exclude<ProjectConfigReadResult['status'], 'valid'> | 'incomplete'; error: string };
@@ -1161,7 +1179,14 @@ export async function handleOpencodeRoutes(
     try {
       const body = await parseJsonBody<{ projectId?: string }>(req);
       if (!body.projectId) throw new Error('Missing project id');
+      const activeProject = await ctx.opencodeProjectStore.getActiveProject();
+      if (activeProject?.id === body.projectId) {
+        await closeAgentBrowserForProject(ctx, activeProject.path);
+      }
       await ctx.opencodeProjectStore.removeProject(body.projectId);
+      if (activeProject?.id === body.projectId) {
+        await closeAgentBrowserForProject(ctx, activeProject.path);
+      }
       await sendProjectSnapshot(res, ctx, { success: true, removedProjectId: body.projectId });
     } catch (error) {
       sendJson(res, 500, { success: false, error: String(error) });
@@ -1193,7 +1218,14 @@ export async function handleOpencodeRoutes(
         sendProjectActivationFailure(res, projectCheck);
         return true;
       }
+      const activeProject = await ctx.opencodeProjectStore.getActiveProject();
+      if (activeProject?.id !== body.projectId && activeProject) {
+        await closeAgentBrowserForProject(ctx, activeProject.path);
+      }
       const project = await ctx.opencodeProjectStore.setActiveProject(body.projectId);
+      if (activeProject?.id !== body.projectId && activeProject) {
+        await closeAgentBrowserForProject(ctx, activeProject.path);
+      }
       await sendProjectSnapshot(res, ctx, { success: true, project });
     } catch (error) {
       sendJson(res, 500, { success: false, error: String(error) });