feat: migrate ESLint to v9 flat config

- Replace .eslintrc.json with eslint.config.mjs
- Simplify configuration using @antfu/eslint-config
- Add necessary ESLint plugin dependencies
- Disable overly strict style rules
- Set package.json type to module for ESM support
- Fix ESLint disable comment format

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/components/welcome/massive-component.tsx

@@ -37,7 +37,7 @@ export const StarIcon = () => (
   </svg>
 )
 
-export const ChatBtn: FC<{ onClick: () => void; className?: string }> = ({
+export const ChatBtn: FC<{ onClick: () => void, className?: string }> = ({
   className,
   onClick,
 }) => {
@@ -46,7 +46,8 @@ export const ChatBtn: FC<{ onClick: () => void; className?: string }> = ({
     <Button
       type='primary'
       className={cn(className, `space-x-2 flex items-center ${s.customBtn}`)}
-      onClick={onClick}>
+      onClick={onClick}
+    >
       <svg width="20" height="21" viewBox="0 0 20 21" fill="none" xmlns="http://www.w3.org/2000/svg">
         <path fillRule="evenodd" clipRule="evenodd" d="M18 10.5C18 14.366 14.418 17.5 10 17.5C8.58005 17.506 7.17955 17.1698 5.917 16.52L2 17.5L3.338 14.377C2.493 13.267 2 11.934 2 10.5C2 6.634 5.582 3.5 10 3.5C14.418 3.5 18 6.634 18 10.5ZM7 9.5H5V11.5H7V9.5ZM15 9.5H13V11.5H15V9.5ZM9 9.5H11V11.5H9V9.5Z" fill="white" />
       </svg>
@@ -55,7 +56,7 @@ export const ChatBtn: FC<{ onClick: () => void; className?: string }> = ({
   )
 }
 
-export const EditBtn = ({ className, onClick }: { className?: string; onClick: () => void }) => {
+export const EditBtn = ({ className, onClick }: { className?: string, onClick: () => void }) => {
   const { t } = useTranslation()
 
   return (