fix: prevent auth flash on checkout, skip subscription guard on success return

app/checkout/page.tsx

@@ -136,12 +136,13 @@ function CheckoutContent() {
     }
   }, [authLoading, user, router])
 
-  // -- Subscription guard --
+  // -- Subscription guard (skip on success page — it handles its own redirect) --
   useEffect(() => {
+    if (status === 'success') return
     if (subscription && (subscription.subscription_status === 'active' || subscription.subscription_status === 'trialing')) {
       router.replace('/')
     }
-  }, [subscription, router])
+  }, [subscription, status, router])
 
   // -- Param validation --
   useEffect(() => {

app/layout-content.tsx

@@ -98,8 +98,8 @@ function LayoutInner({ children }: { children: React.ReactNode }) {
     return <LoadingOverlay logoSrc="/pulse_icon_no_margins.png" title="Pulse" portal={false} />
   }
 
-  // While auth is loading on a site page, render nothing to prevent flash of public header
-  if (auth.loading && isSitePage) {
+  // While auth is loading on a site or checkout page, render nothing to prevent flash of public header
+  if (auth.loading && (isSitePage || isCheckoutPage)) {
     return null
   }