重构 monorepo 并完善网页端订阅与首页体验

- 迁移为 frontend-web、frontend-electron、backend-web 与 docker 部署结构
- 网页端：订阅门禁二次弹窗、套餐/支付组件化、顶栏分组对齐
- 首页：最近文件与模板库布局优化，缩略图对齐，下载与删除操作
- 新增管理后台、支付与云端文件 API，更新 README 与项目规范

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

frontend-electron/package arm64.json

@@ -0,0 +1,51 @@
+{
+  "name": "SoonDesign",
+  "version": "2.1.248",
+  "description": "tools of design soon files",
+  "main": "main.js",
+  "scripts": {
+    "start": "electron-forge start",
+    "package:x64": "electron-forge package --arch=x64",
+    "package:arm64": "electron-forge package --arch=arm64",
+    "merge": "node ./merge.js",
+    "package:universal": "yarn package:x64 && yarn package:arm64 && yarn merge"
+  },
+  "electronPackagerConfig": {
+    "packageManager": "npm",
+    "icon": "./public/images/favicon.icns"
+  },
+  "config": {
+    "forge": {
+      "packagerConfig": {
+        "icon": "./public/images/favicon.icns"
+      }
+    }
+  },
+  "repository": "",
+  "keywords": [
+    "Electron",
+    "quick",
+    "start",
+    "tutorial",
+    "demo"
+  ],
+  "author": "",
+  "license": "MIT",
+  "devDependencies": {
+    "@electron-forge/cli": "^6.2.0",
+    "electron": "^25.0.0"
+  },
+  "dependencies": {
+    "@electron/remote": "^2.0.8",
+    "buffer": "^6.0.3",
+    "bytenode": "^1.3.4",
+    "create-dmg": "^7.0.0",
+    "electron-squirrel-startup": "^1.0.1",
+    "font-list": "^1.4.2",
+    "jr-qrcode": "^1.1.4",
+    "jsbarcode": "^3.11.5",
+    "less": "^4.1.2",
+    "less-loader": "^10.2.0",
+    "save": "^2.9.0"
+  }
+}