feat(ui): Add spinner for "Downloading..." element in UI and add save icon in config page

spotizerr-ui/src/components/config/WatchTab.tsx

@@ -181,8 +181,13 @@ export function WatchTab() {
             type="submit"
             disabled={mutation.isPending || !!validationError}
             className="px-4 py-2 bg-button-primary hover:bg-button-primary-hover text-button-primary-text rounded-md disabled:opacity-50"
+            title="Save Watch Settings"
           >
-            {mutation.isPending ? "Saving..." : "Save Watch Settings"}
+            {mutation.isPending ? (
+              <img src="/spinner.svg" alt="Saving" className="w-5 h-5 animate-spin logo" />
+            ) : (
+              <img src="/save.svg" alt="Save" className="w-5 h-5 logo" />
+            )}
           </button>
         </div>
       </div>