Add Nemotron Nano test preset and simple quota test
Add ServerPreset.nemotron_nano() method and a basic quota request test
to verify the Nemotron 3 Nano 30B A3B GGUF model works correctly.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
