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/ConfirmPasswordMatch.tsx

@@ -7,7 +7,7 @@ type ConfirmPasswordMatchProps = {
     match: boolean,
     doMatch: () => void,
     passRef: RefObject<HTMLInputElement>,
-    confPassRef: RefObject<HTMLInputElement>
+    confPassRef: RefObject<HTMLInputElement>,
   ) => ReactNode;
 };
 export function ConfirmPasswordMatch({ initialValue, children }: ConfirmPasswordMatchProps) {
@@ -28,7 +28,7 @@ export function ConfirmPasswordMatch({ initialValue, children }: ConfirmPassword
     {
       wait: 500,
       immediate: false,
-    }
+    },
   );
 
   return children(match, doMatch, passRef, confPassRef);