[Bug] Windows v0.2.3 编辑器取得工程所有权后心跳未启动，MCP 显示 connected:false 并拒绝绑定

[lts1091396975-blip]

版本 *

v0.2.3（最新 Release）

平台 *

Windows

涉及功能 *

时间线编辑

问题描述 *

版本

OpenChatCut v0.2.3

平台

Windows 11 x64

涉及功能

• 外部 Agent / MCP
• 编辑器实时桥接
• 内置 Agent 工具调用
• 工程所有权租约

问题描述

OpenChatCut 本地 MCP 服务能够正常启动、鉴权、初始化并列出工程，但打开目标工程后，编辑器只取得了 browser ownership，编辑桥没有保持在线。

openchatcut_status 同时出现以下矛盾状态：

• 工程存在 editor 注册记录；
• connected:false；
• connectedProjectIds 为空；
• MCP 只暴露 30 个 server-direct 工具；
• 编辑器记录的 toolCount 为 118；
• 调用 target_project 时却提示工程已有活动编辑器。

错误信息：

Project <projectId> already has an active browser or offline editor.

因此 MCP 无法绑定目标工程，也无法执行：
target_project
begin_edit_session
read_project

与此同时，OpenChatCut 内置 Agent 在尝试读取工程时返回：
code-mode host is disabled




### 复现步骤 *

1.启动 Windows 桌面版 OpenChatCut v0.2.3。
2. 打开一个已有工程。
3. 通过外部 MCP 调用 openchatcut_status。
4. 可以看到编辑器已注册，但 connected:false。
5. 调用 target_project 并传入该工程 ID。
6. MCP 返回：
Project <projectId> already has an active browser or offline editor.
7.在内置 Agent 中要求只读当前工程信息。
8. 内置 Agent 返回：
code-mode host is disabled

### 期望行为 *

打开工程后：
1. 编辑器注册并保持心跳；
2. openchatcut_status 返回：
{
  "connectedProjectIds": ["<projectId>"],
  "editors": [
    {
      "projectId": "<projectId>",
      "connected": true,
      "toolCount": 118
    }
  ]
}
3.外部 MCP 可以成功执行：
target_project
begin_edit_session
read_project
4.如果编辑桥启动失败，应立即释放 browser ownership，避免工程处于既不能在线绑定、也不能离线绑定的状态。
5. UI 应显示明确的桥接失败原因，而不是只留下 connected:false。

### 实际行为 *

MCP 无法绑定目标工程，也无法执行：
target_project
begin_edit_session
read_project

与此同时，OpenChatCut 内置 Agent 在尝试读取工程时返回：
code-mode host is disabled

### 素材信息

_No response_

### 截图 / 日志 / 报错

<img width="1785" height="1227" alt="Image" src="https://github.com/user-attachments/assets/3c69868c-f7ab-42fc-a69a-9042c7d25351" />

MCP 状态输出中同时包含 `connected:false` 和 `already has a

[0xsline]

Thanks for the detailed report. Root cause found and fixed on main (d899791).

Root cause

The editor bridge heartbeat is a timer-driven long poll: the renderer calls nextEditorCall in a loop and every touch refreshes lastSeen (server/external-agent/broker.ts, touch inside the poll loop). Online state = now - lastSeen < 35_000 (server/external-agent/broker-registry.ts:228).

Electron throttles background-window timers by default (backgroundThrottling defaults to true). Neither editor window set it, so minimizing or covering the editor window stretched the poll cadence far beyond 35s → lastSeen expired → connected:false, while the registration itself stayed in place → MCP got "already has an active browser or offline editor". That matches your symptom exactly (registered but not connected, blocked binding).

This is not Windows-only: every desktop platform had the same default. It surfaced on Windows because the workflow switches windows frequently.

Fix

desktop/main.ts now sets backgroundThrottling: false on both the main editor window and the transcript window, so the heartbeat keeps running in the background. desktop/desktop.verify.ts asserts every webPreferences block carries the flag.

About "code-mode host is disabled"

That message does not exist anywhere in this repository — I checked both v0.2.3 and main (git grep across src/ and server/). It comes from your external bridge layer (MCP client / code-mode host), not from OpenChatCut. If you can paste where you saw it, I can tell you exactly which side emits it.

Please verify

The fix ships with the next desktop build (after v0.2.4, which was tagged before this commit). On the Windows build: open a project, minimize the window for a minute, then openchatcut_status should keep connected: true and target_project should bind normally. If it still fails, please attach the renderer console (DevTools) and any server logs so I can trace the remaining gap.

[0xsline]

The fix is shipped in v0.2.5 — please test on the new build: open a project, minimize the window for a minute or two, then check openchatcut_status keeps connected:true and target_project binds normally.

The desktop smoke tests on all three platforms now assert background throttling is disabled at runtime, so this class of regression is gated in CI.