feat: migrate to Cloudflare Workers with icon and version upload

Replace Express/SQLite and web/ with frontend/, worker/, and wrangler deploy. Add optional app icon upload, date-based app_version, and build-app workflow input.

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

package.json

@@ -4,22 +4,21 @@
   "version": "0.1.0",
   "type": "module",
   "workspaces": [
-    "web",
-    "server",
+    "frontend",
+    "worker",
     "template"
   ],
   "scripts": {
-    "dev": "concurrently -n server,web -c blue,green \"npm run dev:server\" \"npm run dev:web:wait\"",
-    "dev:web:wait": "wait-on http://127.0.0.1:3001/api/health -t 120000 && npm run dev -w web",
-    "dev:web": "npm run dev -w web",
-    "dev:server": "npm run dev -w server",
-    "build": "npm run build -w web && npm run build -w server",
-    "start": "npm run start -w server"
+    "dev": "concurrently -n web,worker -c green,blue \"npm run dev -w frontend\" \"wrangler dev\"",
+    "build": "npm run build -w frontend",
+    "deploy": "npm run build && wrangler deploy",
+    "db:migrate:local": "wrangler d1 migrations apply web2app --local",
+    "db:migrate:remote": "wrangler d1 migrations apply web2app --remote"
   },
   "devDependencies": {
     "adm-zip": "^0.5.17",
     "concurrently": "^9.1.2",
     "typescript": "~5.6.2",
-    "wait-on": "^8.0.5"
+    "wrangler": "^3.99.0"
   }
 }