v0.6.0-rc38

Improve model validation to prevent empty --model arguments

- Strengthen isValidModelName validation to catch null, undefined, empty strings
- Remove redundant model && check since isValidModelName handles null cases
- Add modelType to debug logging for better troubleshooting
- Update package version to 1.0.7

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>