fix(xiaohongshu): retry once when first pass returns empty results

[leozejia]

Summary

Improve xiaohongshu search stability by retrying once when the first page render returns an empty result set.

Changes

• update src/clis/xiaohongshu/search.ts
  • wrap extraction in a single-attempt function
  • retry one extra navigation when first attempt returns zero results
• update src/clis/xiaohongshu/search.test.ts
  • add regression test for first empty, second non-empty behavior

Out of Scope

• no changes to global workspace behavior
• no changes to daemon-level retry logic

Validation

• npx vitest --project adapter src/clis/xiaohongshu/search.test.ts