docs: add Xquik remote spec example

[kriptoburak]

Summary

• Add a remote API example for Xquik's published OpenAPI document.
• Show how to keep the x-api-key credential in .apifable/auth.json with ${XQUIK_API_KEY}.
• Point users at Xquik's Tweets, Trends, and Users tags as useful apifable inspection targets.

Validation

• git diff --check
• pnpm install --frozen-lockfile
• pnpm fmt README.md --check

[ycs77]

Hi, thanks for the PR! That said, I don't plan to include integration guides for specific third-party platforms in this project. I'd suggest documenting these usage instructions in your own platform's documentation instead, where they'll be a better fit for your users.

Thanks for understanding!