Add build testing and pre-commit hooks

- Add test-build.js script to verify standalone build locally
- Add pre-commit hook with security, build, and test checks
- Copy required-server-files.json to root of standalone for Amplify
- Add husky for automatic pre-commit validation

This ensures we test builds locally before pushing

amplify.yml

@@ -11,6 +11,7 @@ frontend:
       commands:
         - npm run build
         - cp -r .next/static .next/standalone/.next/
+        - cp .next/standalone/.next/required-server-files.json .next/standalone/
   artifacts:
     baseDirectory: .next/standalone
     files: