fix: daemon 子进程 spawn 跨平台修复 + CliLaunchSpec 集中化重构

- 新建 src/utils/cliLaunch.ts: 集中化 CLI 子进程启动层
  - buildCliLaunch(): 标准化启动规范（execArgv snapshot + bundled mode 检测）
  - spawnCli(): 统一 spawn（自动 windowsHide）
  - quoteCliLaunch(): tmux shell 引用
- 修复 --daemon-worker=kind 等号格式解析（cli.tsx）
- 修复 daemon/bg fast path 缺少 setShellIfWindows()（Windows git-bash 发现）
- 修复 checkPathExists 用 execSync('dir') 改为 existsSync（消除 cmd.exe 弹窗）
- 修复 CLAUDE_CODE_GIT_BASH_PATH env 传播给子进程
- 7 个 spawn 站点迁移到 CliLaunchSpec
- BgEngine 接口新增 supportsInteractiveInput capability
- daemon bg 无 -p 时 detached 引擎给出清晰错误提示

src/commands/remoteControlServer/remoteControlServer.tsx

@@ -1,4 +1,4 @@
-import { spawn, type ChildProcess } from 'child_process';
+import { type ChildProcess } from 'child_process';
 import { resolve } from 'path';
 import * as React from 'react';
 import { useEffect, useState } from 'react';
@@ -10,6 +10,7 @@ import { ListItem } from '../../components/design-system/ListItem.js';
 import { useRegisterOverlay } from '../../context/overlayContext.js';
 import { Box, Text } from '@anthropic/ink';
 import { useKeybindings } from '../../keybindings/useKeybinding.js';
+import { buildCliLaunch, spawnCli } from '../../utils/cliLaunch.js';
 import type { ToolUseContext } from '../../Tool.js';
 import type { LocalJSXCommandContext, LocalJSXCommandOnDone } from '../../types/command.js';
 import { errorMessage } from '../../utils/errors.js';
@@ -202,9 +203,9 @@ async function checkPrerequisites(): Promise<string | null> {
 function startDaemon(): void {
   const dir = resolve('.');
 
-  const execArgs = [...process.execArgv, process.argv[1]!, 'daemon', 'start', `--dir=${dir}`];
+  const launch = buildCliLaunch(['daemon', 'start', `--dir=${dir}`]);
 
-  const child = spawn(process.execPath, execArgs, {
+  const child = spawnCli(launch, {
     cwd: dir,
     stdio: ['ignore', 'pipe', 'pipe'],
     detached: false,