- Reorder shutdown sequence to close pairing operations before DNSPass
- Add proper tracking and cleanup of active Autopass.pair() operations
- Handle shared corestore conflicts between pairing ops and main DNSPass
- Ignore expected "store already closed" errors from pairing operations
- Consolidate all Autopass resource cleanup in PHASE 2.5
This fixes the "Corestore is closed" uncaught exceptions and corruption
that occurred when both pairing operations and DNSPass tried to close
the same shared corestore during shutdown.