- Expand OAuth scope to include read:user for full profile access
- Add GitHubUserInfo struct with Login, Email, Name fields
- Update FetchUserInfo to return complete user profile
- Add Email and Name fields to CopilotTokenStorage and CopilotAuthBundle
- Fix provider string bug: 'github' -> 'github-copilot' in auth_files.go
- Fix semantic bug: email field was storing username
- Update Label to prefer email over username in both CLI and Web API paths
- Add 9 unit tests covering new functionality