[codex] Polish docs hero and Pages actions

[YSCJRH]

Summary

• Stabilizes the Chinese /zh/docs/ hero heading with an intentional two-line break so it no longer wraps into awkward single-character fragments.
• Keeps the existing SEO title and docs task flow intact.
• Upgrades the Pages deployment actions to actions/upload-pages-artifact@v5 and actions/deploy-pages@v5 to address the Node 20 annotation from the previous deployment.

Validation

• git diff --check
• corepack pnpm build:site
• corepack pnpm seo:check
• node --experimental-strip-types --experimental-test-isolation=none --test scripts/distribution/build-site.test.ts
• corepack pnpm test
• corepack pnpm typecheck
• corepack pnpm demo:fixture
• corepack pnpm pack:cli:dry-run
• Local browser visual check on http://127.0.0.1:4174/zh/docs/ and /en/docs/

Truth sync notes

• Latest release rechecked: v0.3.2, published 2026-04-21.
• Umbrella issue rechecked: Roadmap: activation and adoption hardening #33 Roadmap: activation and adoption hardening is still open.
• No scoring, review, download-count, npm availability, or AI answer ranking promises were added.