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/lobby/LobbyHeader.tsx

@@ -132,7 +132,7 @@ const LobbyMenu = forwardRef<HTMLDivElement, LobbyMenuProps>(
         </Box>
       </Menu>
     );
-  }
+  },
 );
 
 type LobbyHeaderProps = {
@@ -150,7 +150,7 @@ export function LobbyHeader({ showProfile, powerLevels }: LobbyHeaderProps) {
   const name = useRoomName(space);
   const avatarMxc = useRoomAvatar(space);
   const avatarUrl = avatarMxc
-    ? mxcUrlToHttp(mx, avatarMxc, useAuthentication, 96, 96, 'crop') ?? undefined
+    ? (mxcUrlToHttp(mx, avatarMxc, useAuthentication, 96, 96, 'crop') ?? undefined)
     : undefined;
 
   const handleOpenMenu: MouseEventHandler<HTMLButtonElement> = (evt) => {