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/components/SpecVersionsLoader.tsx

@@ -15,7 +15,7 @@ export function SpecVersionsLoader({
   children,
 }: SpecVersionsLoaderProps) {
   const [state, load] = useAsyncCallback(
-    useCallback(() => specVersions(fetch, baseUrl), [baseUrl])
+    useCallback(() => specVersions(fetch, baseUrl), [baseUrl]),
   );
   const [ignoreError, setIgnoreError] = useState(false);
 
@@ -38,6 +38,6 @@ export function SpecVersionsLoader({
       ? state.data
       : {
           versions: [],
-        }
+        },
   );
 }