feat: link homepage Open Lab banner to standalone app

[lksbrssr]

Vercel preview

https://plrdorg-git-feat-open-lab-banner-protocol.vercel.app/

READY preview at exact PR head efcc12dd87c74290c91b187a9cef1d184b734a04; hosted homepage and exact banner destination verified in the browser. No production merge.

Summary

Adds the homepage Introducing Open Lab banner directly after the hero and before Focus Areas. Clicking Explore the lab → navigates to the separately hosted app at https://open-lab-two.vercel.app/.

This is the small, website-only successor to the banner in #162. It does not include the old embedded /lab/ prototype, app dependencies, OAuth configuration, DNS changes, or a production merge. It preserves the previously developed banner copy and uses a standard same-tab link (including native keyboard/modifier behavior).

Verification

• Frozen pnpm 10 install; no dependency or lock changes.
• 116 tests passed, zero failed/skipped, including RED/GREEN tests for exact destination, placement, native anchor semantics, and label contrast.
• TypeScript and production build passed. Build worker count was temporarily capped for the local container only; the cap is not in this PR. Existing upstream source/cache warnings remain unrelated.
• Actual production-built localhost browser: 1440px light/dark, 390px mobile; no banner overflow; native Enter and pointer navigation to the standalone app verified.
• Independent review caught low label contrast; corrected and retested. Final computed contrast: 6.38:1 light / 5.40:1 dark.
• No account login or public app write was attempted.

Screenshots

Actual local production-build captures of runtime source a88b10e54ecbf36b7e96f71fb482aaf329d75ae3 (final head adds evidence only), not hosted-preview captures. Scrolled to show the banner and its neighbors.

Desktop

Mobile — 390px

Dark mode

[vercel]

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Project	Deployment	Actions	Updated
plrd.org	Ready	Preview	Sep 15, 2026 3:25pm UTC