Fix player fullscreen issue (#292)

* refactor: 💡 layout grid columns

* fix: 🐛 fix issue where player stays at fullscreen size on exit

✅ Closes: ICU-9456

ui/admin/app/styles/app.scss

@@ -880,7 +880,7 @@
 .layout-sidebar {
   display: grid;
   grid-template-areas: 'body body sidebar';
-  grid-template-columns: auto auto 300px;
+  grid-template-columns: 1fr 1fr 300px;
   grid-template-rows: auto 1fr;
   gap: 2rem;
 
@@ -904,6 +904,10 @@
       'sidebar';
     grid-template-columns: auto;
 
+    .layout-sidebar-body {
+      min-width: 0;
+    }
+
     .layout-sidebar-sidebar {
       max-width: 300px;
     }