added updater and fixed fonts

src/components/layout/AppShell.tsx

@@ -5,6 +5,7 @@ import LeftPanel from './LeftPanel';
 import CenterPanel from './CenterPanel';
 import RightPanel from './RightPanel';
 import ConfigScreen from '../config/ConfigScreen';
+import UpdateChecker from '../update/UpdateChecker';
 import styles from './AppShell.module.css';
 
 export default function AppShell() {
@@ -46,6 +47,7 @@ export default function AppShell() {
       <header className={styles.header}>
         <span className={`${styles.title} font-cinzel`}>Artificer's Scrollwork</span>
         <div className={styles.headerActions}>
+          <UpdateChecker />
           <button
             className={styles.headerBtn}
             onClick={handleIndexAssets}