Support explicit proxy disabling and ambient proxy fallback without leaking env state into config.
Improve first-run detection, endpoint-specific error messaging, diff exclusions, and runtime helper boundaries covered by unit tests.
Add comprehensive setup command with provider selection, API key
configuration, and model selection. Include error recovery for
model-not-found scenarios with suggested alternatives and automatic
retry functionality. Update Anthropic model list with latest versions
and add provider metadata for better user experience.
