qml QEChannelDetails: show currentFeerate

related https://github.com/spesmilo/electrum/issues/8863

electrum/gui/qml/components/ChannelDetails.qml

@@ -256,6 +256,18 @@ Pane {
                         text: channeldetails.channelType
                     }
 
+                    Label {
+                        text: qsTr('Current feerate')
+                        color: Material.accentColor
+                        visible: channeldetails.currentFeerate
+                    }
+
+                    Label {
+                        Layout.fillWidth: true
+                        text: channeldetails.currentFeerate
+                        visible: channeldetails.currentFeerate
+                    }
+
                     Label {
                         visible: channeldetails.isBackup
                         text: qsTr('Backup type')

electrum/gui/qml/qechanneldetails.py

@@ -111,6 +111,13 @@ class QEChannelDetails(AuthMixin, QObject, QtEventListener):
         rsa = self._channel.get_remote_scid_alias()
         return format_short_id(rsa) if rsa else ''
 
+    @pyqtProperty(str, notify=channelChanged)
+    def currentFeerate(self):
+        if self._channel.is_backup():
+            return ''
+        assert isinstance(self._channel, Channel)
+        return self._wallet.wallet.config.format_fee_rate(4 * self._channel.get_latest_feerate(LOCAL))
+
     @pyqtProperty(str, notify=channelChanged)
     def state(self):
         return self._channel.get_state_for_GUI()