feat: 实现笔临 P0/P1 Electron 桌面应用 v0.1.0

交付写作核心（TipTap、自动保存、分卷分章）、Onboarding、7 主题与双语 i18n、快捷键设置；主进程使用 node:sqlite；补全 Vitest 与 Playwright E2E；统一 design/ 目录并移除 desigin 拼写错误路径。

Co-authored-by: Cursor <cursoragent@cursor.com>

src/main/index.ts

@@ -0,0 +1,79 @@
+import { app, BrowserWindow, ipcMain } from 'electron'
+import { existsSync } from 'fs'
+import { join } from 'path'
+import { IPC } from '../shared/ipc-channels'
+import { getShortcutManager, registerIpc } from './ipc/register'
+import { closeAllBookDbs } from './db/connection'
+
+if (process.env.BILIN_E2E === '1' && process.env.BILIN_E2E_USER_DATA) {
+  app.setPath('userData', process.env.BILIN_E2E_USER_DATA)
+}
+
+let mainWindow: BrowserWindow | null = null
+
+function preloadPath(): string {
+  const dir = join(__dirname, '../preload')
+  const mjs = join(dir, 'index.mjs')
+  if (existsSync(mjs)) return mjs
+  return join(dir, 'index.js')
+}
+
+function createWindow(): void {  mainWindow = new BrowserWindow({
+    width: 1280,
+    height: 800,
+    minWidth: 960,
+    minHeight: 600,
+    frame: false,
+    titleBarStyle: 'hidden',
+    webPreferences: {
+      preload: preloadPath(),
+      contextIsolation: true,
+      nodeIntegration: false
+    }
+  })
+
+  if (process.env.ELECTRON_RENDERER_URL) {
+    mainWindow.loadURL(process.env.ELECTRON_RENDERER_URL)
+  } else {
+    mainWindow.loadFile(join(__dirname, '../renderer/index.html'))
+  }
+
+  mainWindow.on('closed', () => {
+    mainWindow = null
+  })
+
+  getShortcutManager()?.setWindow(mainWindow)
+}
+
+app.whenReady().then(() => {
+  registerIpc()
+
+  ipcMain.handle(IPC.WINDOW_MINIMIZE, (event) => {
+    BrowserWindow.fromWebContents(event.sender)?.minimize()
+  })
+  ipcMain.handle(IPC.WINDOW_MAXIMIZE, (event) => {
+    const win = BrowserWindow.fromWebContents(event.sender)
+    if (!win) return
+    if (win.isMaximized()) win.unmaximize()
+    else win.maximize()
+  })
+  ipcMain.handle(IPC.WINDOW_CLOSE, (event) => {
+    BrowserWindow.fromWebContents(event.sender)?.close()
+  })
+
+  createWindow()
+})
+
+app.on('window-all-closed', () => {
+  getShortcutManager()?.unregisterAll()
+  closeAllBookDbs()
+  if (process.platform !== 'darwin') app.quit()
+})
+
+app.on('activate', () => {
+  if (BrowserWindow.getAllWindows().length === 0) createWindow()
+})
+
+app.on('will-quit', () => {
+  getShortcutManager()?.unregisterAll()
+})