fix(web): 修复 .soon/模板加载、旧文件兼容与另存为离开提示

- 删除 design1 ui 遗留代码，修复加载竞态与新建不弹保存提示
- cloud-files 归一化旧版 .soon，IndexedDB 写入完成后再跳转设计页
- 模板/本地 .soon 首次保存须另存为，离开前统一确认
- 发版缓存 bust（version.js、soon-cache.js）及宝塔 Nginx 配置文档

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

scripts/write-web-version.ps1

@@ -0,0 +1,21 @@
+# 写入 frontend-web/config/version.js（start.bat / sync-config 自动调用，发版上传前也会更新）
+param([string]$Version = '')
+
+$ErrorActionPreference = 'Stop'
+$Root = Split-Path $PSScriptRoot -Parent
+$WebRoot = Join-Path $Root 'frontend-web'
+
+if (-not $Version) {
+  Push-Location $Root
+  try { $Version = (git rev-parse --short HEAD 2>$null) } finally { Pop-Location }
+  if (-not $Version) { $Version = Get-Date -Format 'yyyyMMddHHmmss' }
+}
+
+$out = @"
+(function () {
+  'use strict';
+  window.SOON_APP_VERSION = '$Version';
+})();
+"@
+$path = Join-Path $WebRoot 'config\version.js'
+[System.IO.File]::WriteAllText($path, $out, (New-Object System.Text.UTF8Encoding $false))