fix(bluetooth): use deleteLater() instead of delete on device removal

[andckadir]

Synchronously deleting BluetoothDevice and BluetoothAdapter with raw
'delete' inside Bluez::onInterfacesRemoved causes a segmentation fault
(SIGSEGV in libQt6QmlModels.so) when a device is unpaired or removed.

When adapter->devices()->removeObject(device) is called, Qt Quick delegate
models and Repeaters bound to the devices list begin teardown and process
model updates. Immediate deletion frees the QObject while active QML
contexts (QQmlDelegateModelItem / QQmlContextData) still reference it
during that event loop cycle.

Using deleteLater() defers deallocation until the event loop finishes
pending QML signal disconnections and delegate cleanups safely.