fix(zhihu): make question runtime-compatible

[KehaoC]

Summary

Fix zhihu question so it works in the real browser runtime again.

The command was using function-style page.evaluate(...), but the runtime only supports string-based evaluate. This PR switches it to the supported form, navigates to the question page first, and keeps the existing auth / fetch error mapping.

Validation

• npx vitest run src/clis/zhihu/question.test.ts
• npm run build
• node dist/main.js zhihu question 2021881398772981878 --limit 2 -f json
  

Closes #604

[KehaoC]

Sorry, here is the image when running.

[Astro-Han]

Reviewed the runtime-compatibility change for zhihu question. I checked the string-based evaluate migration, the added numeric questionId guard, and the updated unit tests. I did not find blocking issues. I also ran npx vitest run src/clis/zhihu/question.test.ts locally on the PR branch, and all 5 tests passed.

[Astro-Han]

Minor: error message formatting for fetch exceptions

When status === 0 and error is present, the current message reads:

Zhihu question answers request failed Failed to fetch

Two consecutive "failed" without a separator reads awkwardly. Suggested fix in question.ts:

const detail = result?.status > 0
  ? `with HTTP ${result.status}`
  : (result?.error ? `: ${result.error}` : '');

This produces Zhihu question answers request failed: Failed to fetch, which is clearer. The corresponding test expectation in question.test.ts should also be updated to match.

Otherwise the PR looks solid — runtime fix is correct, input validation and security hardening are well done. 👍