[Client] Add missing icon

src/client/app/init.ts

@@ -138,6 +138,7 @@ import {
 	faClock as farClock,
 	faCalendarAlt as farCalendarAlt,
 	faHdd as farHdd,
+	faMoon as farMoon,
 } from '@fortawesome/free-regular-svg-icons';
 
 import {
@@ -258,6 +259,7 @@ library.add(
 	farClock,
 	farCalendarAlt,
 	farHdd,
+	farMoon,
 
 	fabTwitter,
 	fabGithub,