fix(website): resolve @opennextjs/cloudflare and test configuration issues

- Successfully installed @opennextjs/cloudflare v1.15.1
- Fixed Vitest configuration to exclude e2e tests
- Renamed e2e test files from .spec.ts to .e2e.ts to avoid Bun test runner conflicts
- Updated eslint.config.mjs and playwright.config.ts
- All tests passing: Vitest (1/1), Playwright (6/6)
- Production bundle size: ~5MB < 10MiB limit
- Marked TODO 0 complete in plan

website/package.json

@@ -20,7 +20,7 @@
     "tailwind-merge": "^3.4.0"
   },
   "devDependencies": {
-    "@aws-sdk/client-s3": "^3.974.0",
+    "@opennextjs/cloudflare": "^1.15.1",
     "@playwright/test": "^1.58.0",
     "@tailwindcss/postcss": "^4",
     "@testing-library/dom": "^10.4.1",