fix: 修复新建项目无响应问题

- 替换 prompt() 为 InputDialog Vue 模态组件
- 替换 alert()/confirm() 为 Electron showMessageBox IPC
- 添加 dialog:showMessage / dialog:showConfirm IPC 通道

electron/main.js

@@ -85,6 +85,28 @@ ipcMain.handle('dialog:saveFile', async (_event, options) => {
   return null
 })
 
+ipcMain.handle('dialog:showMessage', async (_event, options) => {
+  const result = await dialog.showMessageBox(mainWindow, {
+    type: options?.type || 'info',
+    buttons: options?.buttons || ['确定'],
+    title: options?.title || 'Web2App',
+    message: options?.message || ''
+  })
+  return result.response
+})
+
+ipcMain.handle('dialog:showConfirm', async (_event, options) => {
+  const result = await dialog.showMessageBox(mainWindow, {
+    type: 'question',
+    buttons: ['取消', '确定'],
+    defaultId: 1,
+    cancelId: 0,
+    title: options?.title || 'Web2App',
+    message: options?.message || '确认？'
+  })
+  return result.response === 1
+})
+
 ipcMain.handle('dir:readTree', async (_event, dirPath) => {
   return readDirectoryTree(dirPath)
 })