fix(ios): fix thread-safety race in skipDescriptorDiscovery on reconnect#810
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…ect (#809) On reconnect, CoreBluetooth uses cached GATT data and fires didDiscoverCharacteristicsFor near-instantly on the main queue, before the bridge thread's write to skipDescriptorDiscovery is visible — causing the stale false value to be read and the connection to time out. Fix by dispatching setOnConnected synchronously to the main queue, matching the queue CoreBluetooth delegates run on. Apply the same fix to startScanning's scan filter properties for the same reason. Add comments on stateReceiver where the same issue exists but is too slow to manifest.
Async barrier writes in the subscript setter and removeAll() created a window where values were enqueued but not yet committed, causing callbacks to be nil on fast reconnects.
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On reconnect, CoreBluetooth uses cached GATT data and fires didDiscoverCharacteristicsFor near-instantly on the main queue, before the bridge thread's write to skipDescriptorDiscovery is visible — causing the stale false value to be read and the connection to time out.
Fix by dispatching setOnConnected synchronously to the main queue, matching the queue CoreBluetooth delegates run on. Apply the same fix to startScanning's scan filter properties for the same reason. Add comments on stateReceiver where the same issue exists but is too slow to manifest.