### Added
- Added `titlebar-spinner.ts` example extension that shows a braille spinner animation in the terminal title while the agent is working.
- Added `PI_AI_ANTIGRAVITY_VERSION` environment variable documentation to help text ([#1129](https://github.com/badlogic/pi-mono/issues/1129))
- Added `cacheRetention` stream option with provider-specific mappings for prompt cache controls, defaulting to short retention ([#1134](https://github.com/badlogic/pi-mono/issues/1134))