Set disabled items to use disabled property (#7342)

* Closes #7322
- New CSS for `aria-disabled = true` property.
- Changed multiple items to use aria-disabled instead of .disabled, including:
  - Action menu
  - Super menu
  - Notebook drag area
- Tree item style modded to only italicize when is-navigated and is being edited.

* Closes #7322
- New CSS for `aria-disabled = true` property.
- Changed multiple items to use aria-disabled instead of .disabled, including:
  - Action menu
  - Super menu
  - Notebook drag area
- Tree item style modded to only italicize when is-navigated and is being edited.
- Create button sets itself to `disabled` when the editor is in use.

* Closes #7322
- Create button now _actually_ sets itself to `aria-disabled` when the editor is in use.
- CSS removes selector for `.is-editing`.

* fix conflict

---------

Co-authored-by: John Hill <john.c.hill@nasa.gov>

src/api/menu/components/MenuComponent.vue

@@ -28,7 +28,8 @@
             v-for="action in actionGroups"
             :key="action.name"
             role="menuitem"
-            :class="[action.cssClass, action.isDisabled ? 'disabled' : '']"
+            :aria-disabled="action.isDisabled"
+            :class="action.cssClass"
             :aria-label="action.name"
             :title="action.description"
             @click="action.onItemClicked"
@@ -51,7 +52,8 @@
         v-for="action in options.actions"
         :key="action.name"
         role="menuitem"
-        :class="[action.cssClass, action.isDisabled ? 'disabled' : '']"
+        :aria-disabled="action.isDisabled"
+        :class="action.cssClass"
         :aria-label="action.name"
         :title="action.description"
         @click="action.onItemClicked"

src/api/menu/components/SuperMenu.vue

@@ -37,7 +37,8 @@
             v-for="action in actionGroups"
             :key="action.name"
             role="menuitem"
-            :class="[action.cssClass, action.isDisabled ? 'disabled' : '']"
+            :aria-disabled="action.isDisabled"
+            :class="action.cssClass"
             :title="action.description"
             @click="action.onItemClicked"
             @mouseover="toggleItemDescription(action)"