chore: upgrade i18next 26, prettier 3, fontsource-variable, domhandler 6, lint-staged 17

- i18next 23->26 + react-i18next 15->17
- prettier 2->3, reformat all files
- replace @fontsource/inter with @fontsource-variable/inter 5, update import path
- domhandler 5->6 (aligns with transitive deps)
- lint-staged 16->17

src/app/features/common-settings/general/RoomEncryption.tsx

@@ -49,7 +49,7 @@ export function RoomEncryption({ permissions }: RoomEncryptionProps) {
       await mx.sendStateEvent(room.roomId, StateEvent.RoomEncryption as any, {
         algorithm: ROOM_ENC_ALGO,
       });
-    }, [mx, room.roomId])
+    }, [mx, room.roomId]),
   );
 
   const enabling = enableState.status === AsyncStatus.Loading;