vercel-react-best-practices

@88lin

React and Next.js performance and engineering-quality guidelines from Vercel Engineering. Use when the task is specifically about React/Next performance, data fetching, server/client rendering, bundle size, hydration, or performance-oriented code review/refactoring. Do NOT use as the default for purely visual UI design or normal frontend creation; prefer impeccable unless performance or React architecture quality is part of the task.