feat: add TweetClaw workflows and quoted post context

[kriptoburak]

Summary

• add a current TweetClaw companion workflow to the English README, Chinese README, and Skill guidance
• include the required install, API key, and OpenClaw tool-allowlist commands
• expand quoted posts from the existing X API response
• include quoted author, full text, and canonical URL in feed-x.json
• preserve quotedTweetId and return quotedTweet: null when X cannot expand a referenced post

Independent Repository Fix

Fixes #20.

The feed generator now requests referenced_tweets.id and referenced_tweets.id.author_id expansions with each existing user-posts request. It builds quoted-post context from includes.tweets and includes.users. This adds no extra X API requests.

Validation

• cd scripts && npm ci
• cd scripts && npm test (3 passed)
• node --check scripts/generate-feed.js
• node --check scripts/prepare-digest.js
• node --check scripts/deliver.js
• JSON parsing for package, lock, source, and config files
• GitHub Markdown rendering for README, README.zh-CN, and SKILL
• local-link validation for all 3 touched documents
• current TweetClaw setup verified against its canonical README
• git diff --check

The branch is rebuilt as one signed commit on the current upstream main head.

[kriptoburak]

Rebuilt this PR on the current main head. It now also fixes #20 by expanding quoted posts from the existing X API response, so the change adds no extra API requests. The TweetClaw setup now matches the canonical install, API key, and OpenClaw allowlist commands. All listed tests and document checks pass, and the single commit is verified. Ready for review.