Add Xquik skill

[kriptoburak]

Summary

• Add an installable Xquik skill under skills/xquik.
• Cover X research, media, follower export, monitors, webhooks, and confirmation-gated action prep.

Validation

• Confirmed no existing Xquik skill, PR, or recent issue.
• Confirmed root MIT license.
• Checked public Xquik docs, website, GitHub repo, and npm package metadata.
• Ran diff whitespace validation.

[kriptoburak]

If this is useful and you merge it after checks pass, feel free to share the PR on X/Twitter and mention my handle, burakbayir. I can repost or retweet it to my 24k followers of developers and power users, which may help more relevant users discover this repo.