ba0b0f6d86
- Added 'commit' model role for dedicated commit message generation. - Exported 'resolveModelOverride' function from model-resolver module for public use. - Refactored model role system to centralize role configuration in MODEL_ROLES registry. - Extracted model resolution utilities into dedicated model-resolver module for improved code organization. - Made 'tag' and 'color' properties optional in ModelRoleInfo interface to support roles without visual indicators. - Enhanced model selector with defensive null/undefined checks for optional role properties.