[codex] Clarify playbooks page copy

[YSCJRH]

Summary

• Reframe the Pages playbooks entry around one user task: use one report recommendation to improve one product page.
• Update the Chinese playbooks page to avoid process-heavy wording such as “修复循环” and focus on report → evidence → page edit → rerun.
• Add zh/playbooks coverage to the site generation test so the localized page cannot drift back to mixed or stale copy.

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
• Browser review on http://127.0.0.1:4174/zh/playbooks/ and /en/playbooks/: key copy present once, no console errors.

Notes

• No scoring, review, download-count, or AI answer ranking claims added.
• Remote truth check before editing: latest release v0.3.2; activation/adoption umbrella issue Roadmap: activation and adoption hardening #33 remains open.