UI tweaks (#22405)

* add shm frame lifetime calculation and update UI for shared memory metrics

* consistent sizing on activity indicator in save buttons

* fix offline overlay overflowing on mobile when in grid mode

web/src/components/settings/ObjectMaskEditPane.tsx

@@ -461,7 +461,7 @@ export default function ObjectMaskEditPane({
                 >
                   {isLoading ? (
                     <div className="flex flex-row items-center gap-2">
-                      <ActivityIndicator />
+                      <ActivityIndicator className="size-4" />
                       <span>{t("button.saving", { ns: "common" })}</span>
                     </div>
                   ) : (