- MCP teardown race: add shutdownGeneration counter to prevent
in-flight connections from resurrecting after disconnectAll
- MCP multi-key disconnect race: replace disconnectedSessions Set
with generation-based Map to track per-session disconnect events
- MCP clients: check shutdownGeneration in stdio/http client
creators before inserting into state.clients
- BackgroundManager: call clearTaskHistoryWhenParentTasksGone after
timer-based task removal in scheduleTaskRemoval and notifyParentSession
- BackgroundManager: clean completedTaskSummaries when parent has
no remaining tasks
- Plugin dispose: remove duplicate tmuxSessionManager.cleanup call
since BackgroundManager.shutdown already handles it via onShutdown
H7: Process 'exit'/'SIGINT' listeners registered per-session were
never removed when all sessions disconnected, accumulating handlers.
- Add unregisterProcessCleanup() called in disconnectAll()
H8: Race condition where disconnectSession() during pending connection
left orphan clients in state.clients.
- Add disconnectedSessions Set to track mid-flight disconnects
- Check disconnect marker after connection resolves, close if stale
- Clear marker on reconnection for same session
Tests: 6 pass (3 disconnect + 3 race)
YeonGyu-Kim