Add OAuth providers to test suite and improve test coverage
Tests updated:
- abort.test.ts: Add Google Gemini CLI, add retries
- agent.test.ts: Add OAuth providers (Anthropic, GitHub Copilot, Gemini CLI, Antigravity), add retries, remove timeouts
- context-overflow.test.ts: Handle Cerebras 429 status code
- image-tool-result.test.ts: Add OAuth providers
- overflow.ts: Detect 429 as overflow for Cerebras
Removed obsolete debug/one-off tests:
- copilot-initiator.test.ts
- gemini-3-flash-tool-calling.test.ts
- google-thought-signature.test.ts
- mistral-debug.test.ts
- mistral-empty-assistant.test.ts
- mistral-sdk.test.ts
Mario Zechner
6a319f9c3c