#7210: docs: cleanup citation artifacts and update twitter URLs to X

<!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR performs small documentation cleanups: it removes stray citation artifacts from `docs/tts.md` and updates the Chinese docs acknowledgements in `docs/zh-CN/index.md` to use `x.com` instead of `twitter.com` profile links. These changes are isolated to docs content and don’t affect runtime behavior, but they do impact link correctness and reader experience in the Mintlify-hosted documentation. <h3>Confidence Score: 4/5</h3> - This PR is safe to merge; changes are isolated to documentation text and links. - Only minor Markdown/link updates were made, with low risk of affecting the product. The main remaining concerns are doc rendering consistency (list formatting) and whether `x.com` is the desired canonical domain for social links. - docs/tts.md (Markdown list rendering); docs/zh-CN/index.md (link canonicalization decision) <!-- greptile_other_comments_section --> _{(2/5) Greptile learns from your feedback when you react with thumbs up/down!} <!-- /greptile_comment -->