fix: clear bluetooth device list when adapter is powered off

When airplane mode is enabled, bluetooth is automatically turned off.
However, the device list was not being cleared, causing residual device
information to be displayed in the bluetooth plugin panel.

This fix ensures that when the bluetooth adapter is powered off, all
device items and models are properly cleared to prevent display issues.

Log: clear bluetooth device list when adapter is powered off
Pms: BUG-338867

Author: yixinshark

plugins/dde-dock/bluetooth/componments/bluetoothadapteritem.cpp

@@ -428,7 +428,16 @@ void BluetoothAdapterItem::initConnect()
     });
 
     connect(m_adapter, &Adapter::poweredChanged, this, [ = ](bool state) {
-        initData();
+        if (state) {
+            // Initialize device list when bluetooth is powered on
+            initData();
+        } else {
+            // Clear device list when bluetooth is powered off
+            qDeleteAll(m_deviceItems);
+            m_deviceItems.clear();
+            m_myDeviceModel->clear();
+            m_otherDeviceModel->clear();
+        }
         m_refreshBtn->setVisible(state);
         m_myDeviceWidget->setVisible(m_myDeviceModel->rowCount() > 0 && state);
         m_otherDeviceListView->setVisible(state && (m_otherDeviceControlWidget->isExpand() || m_myDeviceModel->rowCount() < 1));