Adds new CLI command to fetch tweets from any user's profile timeline. Usage: bird user-tweets @username [-n count] [--pages N] [--json] Features: - GraphQL UserByScreenName for username → userId resolution - Cursor-based pagination with configurable delay (rate-limit safe) - Hard cap of 10 pages to prevent abuse - Input validation via normalizeHandle() Includes 17 unit tests and live smoke test. Co-authored-by: Christian Catalan <[email protected]>