Expose the battery percentage toggle through omarchy.power IPC

omarchy-shell omarchy.power togglePercentage now flips the same setting
the widget's right-click does. Follows the monitor/tailscale pattern:
manageIpc: false so the panel owns the target's single IpcHandler and
can extend it past the inherited lifecycle methods.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

shell/plugins/panels/power/Panel.qml

@@ -10,6 +10,9 @@ Panel {
   id: root
   moduleName: "omarchy.power"
   ipcTarget: "omarchy.power"
+  // manageIpc: false so this panel can own the single IpcHandler the target
+  // permits — needed for the togglePercentage method below.
+  manageIpc: false
   property var batteryInfo: ({})
   property var systemInfo: ({})
   property var profiles: []
@@ -171,6 +174,17 @@ Panel {
     if (root.bar && root.bar.shell) root.bar.shell.updateEntryInline(root.moduleName, root.settings)
   }
 
+  IpcHandler {
+    target: "omarchy.power"
+
+    function open() { root.open() }
+    function close() { root.close() }
+    function show() { root.open() }
+    function hide() { root.close() }
+    function toggle() { root.toggle() }
+    function togglePercentage() { root.togglePercentage() }
+  }
+
   onOpenedChanged: {
     if (opened) {
       if (!batteryPresent) {