fix(expert): make togglePinWithWidth inject optional

The Expert component was crashing in the immersive editor when sending
messages because it expected togglePinWithWidth to be provided by a
parent component. In the immersive editor, Expert is loaded directly
as a route component without the RightDrawer wrapper that provides
this function.

Changed the inject from array to object format with a default no-op
function, allowing the component to work both in the drawer context
and standalone in the immersive editor.

Author: dimitrieh

frontend/src/components/expert/Expert.vue

@@ -74,7 +74,12 @@ export default {
         ExpertRichGuide,
         ExpertRichResources
     },
-    inject: ['togglePinWithWidth'],
+    inject: {
+        togglePinWithWidth: {
+            from: 'togglePinWithWidth',
+            default: () => () => {} // No-op function when not provided
+        }
+    },
     data () {
         return {
             scrollCheckDebounce: null,