Improve RSC pages to follow React on Rails RSC migration guide best practices

[AbanoubGhadban]

Summary

Audit and improve all RSC page implementations in the demo to align with the React on Rails RSC migration guide best practices. The demo serves as a reference for RSC adoption, so each page should showcase recommended patterns.

RSC Pages to Review

• Product Page (/product/rsc) — ProductPageRSC
• Product Search (/product-search/rsc) — ProductSearchRSC
• Dashboard Analytics (/analytics/rsc) — DashboardPageRSC
• Blog Post (/blog/rsc) — BlogPostRSC
• Restaurant Search (/search/rsc) — SearchPageRSC

Areas to Evaluate

Component Organization

• Proper 'use client' boundary placement — only on leaf interactive components
• Server components should not import client-only code
• Verify no unnecessary client components (components that could remain server-side)

Data Fetching & Streaming

• Async prop streaming order is optimized (critical content first)
• Suspense boundaries with meaningful skeleton fallbacks
• Sync vs async prop split follows best practices (minimal sync props for fast initial paint)

Bundle Size

• Confirm heavy libraries (d3, marked, highlight.js) stay server-side in RSC variants
• Verify client JS is minimal (only interactive islands hydrate)
• No unintended client bundle bloat from server component imports

Controller & View Patterns

• stream_react_component_with_async_props usage follows latest API
• emit.call ordering and naming conventions are consistent
• Proper use of enable_async_react_rendering and stream_view_containing_react_components

Error Handling & Loading States

• Error boundaries around async sections
• Skeleton/loading fallbacks for all Suspense boundaries
• Graceful degradation if streaming fails

Performance

• No waterfall data fetching in controllers (parallelize where possible)
• Appropriate highWaterMark settings for streams
• Efficient serialization (no over-fetching data in props)

Acceptance Criteria

• Each RSC page reviewed against migration guide best practices
• Identified improvements documented and implemented
• Demo remains a clear reference for each rendering pattern (SSR vs Client vs RSC)