Fix 80% battery charge limit for Legion Go resetting (#1075)

* Add 80% battery charge limit for Legion Go

* removed UpdateSettings()

not needed, SettingsManager will iterate through all settings on startup anyway

* Fix Legion Go battery charge limit toggle not saving

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Co-authored-by: Plasmid <22126651+PlasmidEve@users.noreply.github.com>
Co-authored-by: Lesueur Benjamin <benjamin.lesueur@live.com>

HandheldCompanion/Views/Pages/DevicePage.xaml.cs

@@ -165,6 +165,9 @@ private void SettingsManager_SettingValueChanged(string? name, object value)
                     case "LegionControllerGyroIndex":
                         ComboBox_GyroController.SelectedIndex = Convert.ToInt32(value);
                         break;
+                    case "LegionBatteryChargeLimit":
+                        Toggle_LegionBatteryChargeLimit.IsOn = Convert.ToBoolean(value);
+                        break;
                     case "SensorSelection":
                         {
                             int idx = Convert.ToInt32(value);