Add x-twitter-scraper skill

[kriptoburak]

Summary

• Adds an x-twitter-scraper skill for Xquik-backed X/Twitter data access, media workflows, monitoring, webhooks, MCP, SDKs, and confirmation-gated writes.
• Wires the skill into .claude-plugin/marketplace.json and the README install/available-skills sections.

Duplicate And Policy Checks

• Checked the default branch for Xquik, x-twitter-scraper, xquik.com, and Xquik-dev; no existing listing found.
• Checked open and closed PRs/issues for the same names and URLs; no duplicates found.
• Followed the README contribution route: new skills/<name>/SKILL.md directory plus marketplace entry.

Validation

• jq empty .claude-plugin/marketplace.json
• Local structural validation for the marketplace entry and skill frontmatter.
• git diff --check
• Source-truth check against https://xquik.com/openapi.json for cited endpoint families and the required tweet-search q parameter.
• Staged diff scan for prohibited references, token-like secrets, literal escaped newlines, em dash, and spaced double-hyphen.
• Link check: 5 public scoped URLs passed; 2 authenticated API examples skipped because they require x-api-key or MCP auth.