Non-blocking session summaries for real-time systems

New async APIs (aget_session_summary()) let Agents and Teams return session summaries without blocking. This aligns with event-driven and streaming architectures, reducing UI latency and improving responsiveness.

Details

• Async parity with existing summary APIs
• Safe to call during long-running operations and streams
• No migration required

Who this is for: Teams building async services, dashboards, or interactive experiences that require live summaries.