Transform the TeaTime Tracker from a toy calculator into a real brew-logging CLI. Add brew entry recording, daily summary reporting, and brew history persistence.

Success

Users can log a brew with type and timestamp, view a daily summary of brews, and brews persist across sessions. All features have CI-validated red/green test coverage.

Policy

All changes must pass TDD red/green evidence with GitHub Actions CI confirmation. No direct pushes to main. Auto-merge only after CI passes on PR.