Implement OpenAI provider for GPT-4, GPT-3.5, and other OpenAI models.
Implementation includes:
- OpenAI SDK integration with API key authentication
- Chat completion with streaming support
- Embeddings generation
- Health checks and model listing
- OpenTelemetry tracing
- Comprehensive test suite with 97% coverage
Follows TDD methodology:
- Written tests first (RED phase)
- Implemented minimal code to pass tests (GREEN phase)
- Code passes typecheck, linter, and all quality gates
Test coverage: 97.18% statements, 97.05% lines
All 22 tests passing
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>