feat(twitter): add --type flag to timeline command

[Astro-Han]

Summary

Closes #83.

• Add --type flag to twitter timeline with choices for-you (default, algorithmic) and following (chronological)
• Both endpoints share the same GraphQL response structure; only the endpoint name, HTTP method, and queryId differ (HomeTimeline GET vs HomeLatestTimeline POST)
• QueryId is resolved dynamically from fa0311/twitter-openapi with hardcoded fallback, validated against /^[A-Za-z0-9_-]+$/ to prevent injection from untrusted upstream

Usage

opencli twitter timeline                        # default: for-you
opencli twitter timeline --type following        # chronological
opencli twitter timeline --type for-you --limit 10

Test plan

• opencli twitter timeline still works as before (default for-you)
• opencli twitter timeline --type following returns chronological timeline
• opencli twitter timeline --type invalid is rejected by choices validation
• npm run typecheck passes

[Astro-Han]

Note: Verified via npm run typecheck (pass) and npx vitest run src/ (301/301 pass). Manual testing of the --type following endpoint requires a logged-in browser session with Twitter cookies, which cannot be automated in CI. The implementation mirrors the existing HomeTimeline pattern with only the GraphQL endpoint name and queryId changed.