Handle OpenCode session events that carry the session ID under properties.info.id or properties.info.sessionID so background tasks and continuation hooks do not miss idle/error/delete events.
Add regression coverage for nested session.idle events completing background tasks and waking continuation hooks.
Add session-status-normalizer to handle session.status events and
convert idle status to synthetic session.idle events. Includes
deduplication logic to prevent duplicate idle events within 500ms.
YeonGyu-Kim