🎨 chore(web): apply ESLint and Prettier auto-fixes (baseline)

- Ran: bun run eslint:fix && bun run lint:fix
- Inserted AGPL license header via eslint-plugin-header
- Enforced no-multiple-empty-lines and other lint rules
- Formatted code using Prettier v3 (@so1ve/prettier-config)
- No functional changes; formatting-only baseline across JS/JSX files

web/src/components/settings/DrawingSetting.jsx

@@ -81,4 +81,4 @@ const DrawingSetting = () => {
   );
 };
 
-export default DrawingSetting; 
+export default DrawingSetting;