Gemini 3 Pro requires thoughtSignature on function call blocks in
subsequent requests. This commit:
- Add thought-signature-store for session-based signature storage
- Extract signature from both streaming (SSE) and non-streaming responses
- Inject signature into functionCall parts on subsequent requests
- Maintain consistent sessionId per fetch instance
Debug logging available via ANTIGRAVITY_DEBUG=1
🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)
- Separate Google Antigravity auth to 'oh-my-opencode/google-auth' subpath
- 'oh-my-opencode/auth' now exports OpenAI Codex auth plugin
- Implement dynamic port allocation to avoid port conflicts
- Add userAgent, requestId, sessionId fields for Antigravity API compatibility
- Add debug logging for troubleshooting (ANTIGRAVITY_DEBUG=1)
🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)
