Previously, unstable agents (gemini models, is_unstable_agent=true) were forced to background mode but returned immediately with task ID. This caused callers to lose visibility into results. Now: launch as background for monitoring stability, but poll and wait for completion, returning actual task output like sync mode. 🤖 Generated with assistance of [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)