- Update CreateCommit to accept separate authorName and authorEmail
- Add GetGitConfig method to read user.name and user.email from config
- GetGitConfig checks local repo config first, then global config
- Update save.go to read author from git config before creating commits
- Update workstream_manager.go to extract author from git commit
- Update daemon/snapshot.go to use proper email for daemon commits
- Update git/rebase.go to preserve author email during rebases
Fixes issue where commits showed 'User <onyx@local>' instead of
actual git user.name and user.email from config.
