Follow-up for salvaged PR #7637. Adds kimi-coding-cn to: - model_normalize.py (prefix strip) - providers.py (models.dev mapping) - runtime_provider.py (credential resolution) - setup.py (model list + setup label) - doctor.py (health check) - trajectory_compressor.py (URL detection) - models_dev.py (registry mapping) - integrations/providers.md (docs)