Add icon preview to menu editor dialog

Co-authored-by: renemadsen <76994+renemadsen@users.noreply.github.com>

Author: Copilot

eform-client/src/app/modules/advanced/modules/navigation-menu/components/menu-item/navigation-menu-item-edit/navigation-menu-item-edit.component.html

@@ -24,6 +24,10 @@ <h3 mat-dialog-title>{{'Edit menu entry' | translate}}</h3>
         placeholder="e.g., home, settings, dashboard"
       >
     </mat-form-field>
+    <div class="d-flex flex-row align-items-center mb-3" *ngIf="item.icon">
+      <span class="me-2">{{ 'Icon preview' | translate }}:</span>
+      <mat-icon id="editIconPreview">{{ item.icon }}</mat-icon>
+    </div>
     <div class="d-flex flex-row align-items-center need-wrapper"
          *ngIf="item.type === menuItemType.CustomLink || item.type === menuItemType.Link">
       <mat-form-field>