[codex] Clarify docs task entry copy

[YSCJRH]

Summary

• Clarifies the Pages docs landing page as a task picker for users who already have an AnswerLens report open.
• Updates Chinese and English docs-entry copy around scorecard reading, failed-check explanation, real-site quickstart, and GitHub Action adoption.
• Extends the build-site test assertions so old instruction-like docs copy does not drift back into /zh/docs/.

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 check on http://127.0.0.1:4174/zh/docs/ and /en/docs/: required copy present, no console errors

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.
• npm view @answerlens/cli still returns 404, so this PR does not add or change npm install availability claims.
• No scoring, review, download-count, or AI answer ranking promises were added.