style(workspace): remove any border or box from doc title emoji

frontend/src/features/workspace/DocumentEditor.tsx

@@ -963,7 +963,7 @@ export const DocumentEditor: React.FC<DocumentEditorProps> = ({
                 <button
                   type="button"
                   onClick={() => canEdit && setShowEmojiPicker((prev) => !prev)}
-                  className="text-2xl sm:text-3xl hover:opacity-80 transition-opacity p-0.5 rounded cursor-pointer select-none"
+                  className="text-2xl sm:text-3xl hover:opacity-80 transition-opacity cursor-pointer select-none leading-none bg-transparent border-0 outline-none p-0 focus:outline-none focus:ring-0 shadow-none"
                   title="Icon ändern"
                 >
                   {doc?.icon || '📝'}