Strip template artifacts and fix lint errors

Remove npm lockfile, unused create-next-app SVGs, project-specific
next.config workarounds, and the unused @remixicon/react and date-fns deps.

Replace three set-state-in-effect patterns with useSyncExternalStore in
use-mobile, DialogPortal, and Carousel; the carousel change also fixes a
leaked reInit listener. yarn lint and yarn build are clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K8PmydbW6A1S2Tw3SFc3Cg

components/ui/dialog.tsx

@@ -19,15 +19,21 @@ function DialogTrigger({
   return <DialogPrimitive.Trigger data-slot="dialog-trigger" {...props} />
 }
 
+const subscribeToNothing = () => () => {}
+
 function DialogPortal({
   ...props
 }: React.ComponentProps<typeof DialogPrimitive.Portal>) {
   // Radix's Portal calls createPortal(children, document.body) as soon as it
   // renders. During static prerendering there's no `document`, so gate the
-  // portal behind an effect that only runs in the browser. Closed dialogs
-  // render nothing on the server anyway, so there's no visual/hydration change.
-  const [mounted, setMounted] = React.useState(false)
-  React.useEffect(() => setMounted(true), [])
+  // portal on the client snapshot, which is only read in the browser. Closed
+  // dialogs render nothing on the server anyway, so there's no visual/
+  // hydration change.
+  const mounted = React.useSyncExternalStore(
+    subscribeToNothing,
+    () => true,
+    () => false
+  )
 
   if (!mounted) return null