ExtensionRunner.emit shared the generic 30s EXTENSION_HANDLER_TIMEOUT_MS budget with every event, including the fire-and-forget session_shutdown teardown event extensions cannot observe. A hung third-party handler — observed on Windows with omp-discord-presence 0.1.2 waiting on a stuck Discord IPC pipe — held AgentSession.dispose() for the full window, making Ctrl+C look ignored for 30s.
session_shutdown now uses a dedicated 2s SESSION_SHUTDOWN_HANDLER_TIMEOUT_MS cap routed through a per-event handlerTimeoutForEvent() lookup so generic and shutdown budgets are independently configurable. The interactive-mode Ctrl+C path adds a defence-in-depth hard-exit: when isShuttingDown is true a fresh Ctrl+C exits with code 130 (the session JSONL has already been sync-flushed by the first press) instead of stacking another no-op shutdown() call.
Fixes#2600
roboomp
b0d0bd5bcb