Fixed error: GitService.init_repo() got an unexpected keyword argument 'default_branch'
The init_repository route was passing default_branch to GitService.init_repo(),
but the method signature didn't accept this parameter.
Changes:
- Added default_branch: Optional[str] = None parameter to init_repo() method
- Updated clone operation to use specified default branch when provided
- Updated method documentation to reflect the new parameter
This allows repositories to be initialized with a specific default branch
as configured in GitServerConfig, while maintaining backward compatibility.