add setting switch

this isnt bound to anything yet

i18n/en.json

@@ -829,6 +829,8 @@
   "empty_trash_confirmation": "Are you sure you want to empty the trash? This will remove all the assets in trash permanently from Immich.\nYou cannot undo this action!",
   "enable": "Enable",
   "enable_biometric_auth_description": "Enter your PIN code to enable biometric authentication",
+  "enable_gcast": "Enable Google Cast",
+  "enable_gcast_description": "Stream your images and video to a Google Cast enabled device. This feature loads external resources from Google in order to work.",
   "enabled": "Enabled",
   "end_date": "End date",
   "enqueued": "Enqueued",

web/src/lib/components/user-settings-page/app-settings.svelte

@@ -168,6 +168,13 @@
           bind:checked={$showDeleteModal}
         />
       </div>
+      <div class="ms-4">
+        <SettingSwitch
+          title={$t('enable_gcast')}
+          subtitle={$t('enable_gcast_description')}
+          bind:checked={$gcastEnabled}
+        />
+      </div>
     </div>
   </div>
 </section>