fork: add worker-test package

- Add packages/worker-test/ for Cloudflare Workers integration testing
- Includes test harness, wrangler config, and test runner

Author: manno23

packages/worker-test/.gitignore

@@ -0,0 +1,35 @@
+# Dependencies
+node_modules/
+dist/
+.env
+.env.local
+.env.*.local
+
+# TypeScript
+*.tsbuildinfo
+
+# Wrangler
+.wrangler/
+worker-configuration.d.ts
+
+# Logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+
+# OS
+.DS_Store
+Thumbs.db
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# Test coverage
+coverage/
+.nyc_output/