* feat: add API key and custom provider configuration
Previously, model setup only offered OAuth login. This adds:
- API key configuration for 17 built-in providers (OpenAI, Anthropic,
Google, Mistral, Groq, xAI, OpenRouter, etc.)
- Custom provider setup via models.json (for Ollama, vLLM, LM Studio,
proxies, or any OpenAI/Anthropic/Google-compatible endpoint)
- Interactive prompts with smart defaults and auto-detection of models
- Verification flow that probes endpoints and provides actionable tips
- Doctor diagnostics for models.json path and missing apiKey warnings
- Dev environment fallback for running without dist/ build artifacts
- Unified auth flow: `feynman model login` now offers both API key
and OAuth options (OAuth-only when a specific provider is given)
New files:
- src/model/models-json.ts: Read/write models.json with proper merging
- src/model/registry.ts: Centralized ModelRegistry creation with modelsJsonPath
- tests/models-json.test.ts: Unit tests for provider config upsert
* fix: harden runtime env and custom provider auth
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Co-authored-by: Advait Paliwal <advaitspaliwal@gmail.com>
