WIP: A simple cli for daily tangled use cases and AI integration. This is for my personal use right now, but happy if others get mileage from it! :)

Add AT-URI utilities and issue validation master

New utilities: - parseAtUri(): Parse AT-URI into components (did, collection, rkey) - resolveHandleToDid(): Resolve handle to DID via AT Protocol - buildRepoAtUri(): Construct repository AT-URI from owner and repo name New validation schemas: - issueTitleSchema: 1-256 characters - issueBodySchema: Optional, max 50,000 characters - atUriSchema: Validate AT-URI format Includes comprehensive test coverage (45 tests passing) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>