fix: serve the website dist so Coolify answers GET /

Nixpacks built Vite but had no production start command, so Coolify returned Cannot GET /.

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

package.json

@@ -32,6 +32,7 @@
     "website:dev": "npm run dev --prefix packages/website",
     "website:build": "npm run build --prefix packages/website",
     "website:preview": "npm run preview --prefix packages/website",
+    "website:start": "npm start --prefix packages/website",
     "website:typecheck": "npm run typecheck --prefix packages/website",
     "install:all": "npm run chrome:install && npm run vscode:install && npm run cli:install && npm run website:install",
     "typecheck:all": "npm run chrome:typecheck && npm run vscode:typecheck && npm run cli:typecheck && npm run website:typecheck",