fix: visually disable/remove interactive elements in non-editable sheets

templates/sheets/shared/components/add-button.hbs

@@ -11,6 +11,7 @@ SPDX-License-Identifier: MIT
 !-- @param title: The title to use for the link element (will be localized)
 !-- @param type: An optional property to use as data-type attribute
 }}
+{{#if @root/editable}}
 <div class="ds4-add-button">
     <a class="control-{{documentType}}" title="{{localize title}}" data-action="create" {{#if type}}data-type="{{type}}"
         {{/if}}>
@@ -18,3 +19,4 @@ SPDX-License-Identifier: MIT
         {{localize "DS4.UserInteractionAdd"}}
     </a>
 </div>
+{{/if}}