refactor(claw): use isFreeModel helper for credit nudge visibility

Replace the hand-rolled Set of free model IDs with a direct call to the
existing isFreeModel() helper, which already covers all free model
detection cases (kilo free models, :free suffix, stealth models, etc.).

Author: RSO

src/app/(app)/claw/components/CreateInstanceCard.tsx

@@ -12,6 +12,7 @@ import { useTRPC } from '@/lib/trpc/utils';
 import type { ModelOption } from '@/components/shared/ModelCombobox';
 import { useUser } from '@/hooks/useUser';
 import { KILO_AUTO_FRONTIER_MODEL, KILO_AUTO_FREE_MODEL } from '@/lib/kilo-auto-model';
+import { isFreeModel } from '@/lib/models';
 import { Button } from '@/components/ui/button';
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
 import { getCreateModelOptions } from './modelSupport';
@@ -80,6 +81,7 @@ export function CreateInstanceCard({
   const isPaymentReturn = searchParams.get('payment') === 'success';
   const hasAutoProvisioned = useRef(false);
 
+
   useEffect(() => {
     if (hasAppliedDefault.current || selectedModel !== '' || modelOptions.length === 0) return;
     if (isLoadingUser) return;
@@ -176,8 +178,7 @@ export function CreateInstanceCard({
     );
   }
 
-  const needsCredits =
-    !hasCredits && selectedModel !== '' && selectedModel !== KILO_AUTO_FREE_MODEL.id;
+  const needsCredits = !hasCredits && selectedModel !== '' && !isFreeModel(selectedModel);
 
   return (
     <Card>