feat(web): refine typography and skill discovery

[dirtybits]

Summary

• Establish semantic font roles: Crimson Pro for font-title / font-display, Inter for font-sans, and Inconsolata for font-mono.
• Register the roles in Tailwind v4 so generated variants, including Markdown headings, use the intended fonts.
• Remove the homepage feature strip and add a responsive featured-skills carousel.
• Replace marketplace page-number pagination with append-only View more, retry, visible-count, and end-of-list states.
• Keep the final-batch loading button visible and disabled until its request completes.
• Reconcile current main while retaining the mobile theme control and merged API input guards.

Verification

• Node 24: npm run format:check, npm run lint:web, and npm run typecheck passed.
• npm test --workspace @agentvouch/web -- --maxWorkers=1 --no-fileParallelism: 129 files / 953 tests passed.
• Four new typography tests compile the actual stylesheet and font variants; they failed before the theme mapping and pass afterward.
• npm exec --workspace @agentvouch/web -- next build --webpack passed, including 156 generated pages. The existing non-blocking ox dynamic-dependency warning remains.
• Browser checks: marketplace 9 to 18 cards, search after appending resets to the matching result, and final-batch loading transitions from 9/12 to 12/12.
• Browser checks: narrow-layout carousel navigation, light/dark themes, skill detail rendered font families, and no console errors during the checked flows.
• Public production homepage, marketplace, dashboard, and sign-in loaded during the reported availability investigation; no production runtime errors were found.

Not verified

• Real wallet signatures, paid checkout, and authenticated account actions were not exercised.
• The user's reported site failure was not reproduced on public production routes. The local preview had been stopped and has been restored separately.