Add trends UI with admin and user settings (#11502)

app/javascript/mastodon/initial_state.js

@@ -22,5 +22,6 @@ export const isStaff = getMeta('is_staff');
 export const forceSingleColumn = !getMeta('advanced_layout');
 export const useBlurhash = getMeta('use_blurhash');
 export const usePendingItems = getMeta('use_pending_items');
+export const showTrends = getMeta('trends');
 
 export default initialState;