refactor: 迁移至 electron-vite 官方推荐目录结构

- electron/* -> src/main/* (主进程)
- electron/preload.ts -> src/preload/index.ts (预加载)
- src/electron-api.d.ts -> src/preload/index.d.ts (类型声明)
- src/* -> src/renderer/src/* (渲染进程)
- src/index.html -> src/renderer/index.html
- electron.vite.config.ts 简化为自动入口检测 (零配置)
- tsconfig.app.json -> tsconfig.web.json, 更新 includes/paths
- 构建产物 dist-electron/ -> out/ (修复 main/preload 输出覆盖 bug)
- 更新 package.json main 字段 + electron-builder files
- 更新 .gitignore + eslint ignores
- 更新 AGENTS.md 架构文档

src/main/updater.ts

@@ -0,0 +1,74 @@
+// electron-updater is CommonJS with a lazy getter for `autoUpdater`, so a named
+// ESM import fails at runtime under Node ESM (cjs-module-lexer can't detect it).
+// Use the default interop import and access the instance lazily inside initUpdater
+// (after app.whenReady), matching the original intended evaluation timing.
+import electronUpdater from 'electron-updater'
+import { BrowserWindow, ipcMain } from 'electron'
+
+let mainWindow: BrowserWindow | null = null
+
+export function initUpdater(win: BrowserWindow): void {
+  mainWindow = win
+  const autoUpdater = electronUpdater.autoUpdater
+
+  // 检查更新
+  ipcMain.handle('updater:check', async () => {
+    try {
+      const result = await autoUpdater.checkForUpdates()
+      return result?.updateInfo ? { available: true, version: result.updateInfo.version } : { available: false }
+    } catch {
+      return { available: false }
+    }
+  })
+
+  // 下载更新
+  ipcMain.handle('updater:download', async () => {
+    try {
+      await autoUpdater.downloadUpdate()
+      return { success: true }
+    } catch (err: any) {
+      return { success: false, error: err.message }
+    }
+  })
+
+  // 安装更新
+  ipcMain.handle('updater:install', () => {
+    autoUpdater.quitAndInstall()
+  })
+
+  autoUpdater.autoDownload = false
+
+  autoUpdater.on('checking-for-update', () => {
+    mainWindow?.webContents.send('updater:status', { status: 'checking' })
+  })
+
+  autoUpdater.on('update-available', (info) => {
+    mainWindow?.webContents.send('updater:status', {
+      status: 'available',
+      version: info.version,
+      releaseNotes: info.releaseNotes,
+    })
+  })
+
+  autoUpdater.on('update-not-available', () => {
+    mainWindow?.webContents.send('updater:status', { status: 'not-available' })
+  })
+
+  autoUpdater.on('download-progress', (progress) => {
+    mainWindow?.webContents.send('updater:status', {
+      status: 'downloading',
+      percent: progress.percent,
+      transferred: progress.transferred,
+      total: progress.total,
+      bytesPerSecond: progress.bytesPerSecond,
+    })
+  })
+
+  autoUpdater.on('update-downloaded', () => {
+    mainWindow?.webContents.send('updater:status', { status: 'downloaded' })
+  })
+
+  autoUpdater.on('error', (err) => {
+    mainWindow?.webContents.send('updater:status', { status: 'error', message: err.message })
+  })
+}