- Updated `ideType` to `ANTIGRAVITY` in request payload.
- Introduced tier-selection logic to determine default tier for onboarding.
- Added `antigravityOnboardUser` function for project ID retrieval via polling.
- Enhanced error handling and response decoding for onboarding flow.
feat(oauth): add support for customizable OAuth callback ports
- Introduced `oauth-callback-port` flag to override default callback ports.
- Updated SDK and login flows for `iflow`, `gemini`, `antigravity`, `codex`, `claude`, and `openai` to respect configurable callback ports.
- Refactored internal OAuth servers to dynamically assign ports based on the provided options.
- Revised tests and documentation to reflect the new flag and behavior.
- Replaced `http.DefaultClient` with a configurable `http.Client` instance for Antigravity OAuth flow methods.
- Updated `exchangeAntigravityCode` and `fetchAntigravityUserInfo` to accept `httpClient` as a parameter.
- Added `util.SetProxy` usage to initialize the `httpClient` with proxy support.
- Implemented OAuth login flow for the Antigravity provider in `auth/antigravity.go`.
- Added `AntigravityExecutor` for handling requests and streaming via Antigravity APIs.
- Created `antigravity_login.go` command for triggering Antigravity authentication.
- Introduced OpenAI-to-Antigravity translation logic in `translator/antigravity/openai/chat-completions`.
**refactor(translator, executor): update Gemini CLI response translation and add Antigravity payload customization**
- Renamed Gemini CLI translation methods to align with response handling (`ConvertGeminiCliResponseToGemini` and `ConvertGeminiCliResponseToGeminiNonStream`).
- Updated `init.go` to reflect these method changes.
- Introduced `geminiToAntigravity` function to embed metadata (`model`, `userAgent`, `project`, etc.) into Antigravity payloads.
- Added random project, request, and session ID generators for enhanced tracking.
- Streamlined `buildRequest` to use `geminiToAntigravity` transformation before request execution.