Perf/lighthouse check/products

[bittensorrider]

Summary

Performance improvements for /products/[slug] based on Lighthouse audits:

• bfcache — Replaced force-dynamic with ISR (revalidate = 60, generateStaticParams); annotation mutations call revalidatePath
• Render-blocking CSS — Inline Tailwind at build time via scripts/generate-inline-styles.mjs; moved schema-only .md-preview styles to a separate file
• Legacy JavaScript — Stubbed Next.js polyfill module for modern browsers; added explicit browserslist targets
• Unused JavaScript — Server-rendered NavBar (pathname via middleware); lazy-load annotation popover on click; dynamic ReExtractButton on product pages

Test plan

• npm run build && npm start
• Lighthouse on /products/r770 in Incognito (extensions off)
• Confirm bfcache, render-blocking CSS, and legacy JS insights are resolved
• Verify annotation buttons and Re-extract still work after interaction
• Verify NavBar active state on navigation

Screenshots

Before Fix

After Fix