feat: add past-due payment banner to dashboard

Show an amber banner to logged-in users whose grace_period_until is set,
linking to the Stripe Customer Portal to update their card.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

resources/views/dashboard.blade.php

@@ -1,5 +1,6 @@
 <x-layouts::app :title="__('Dashboard')">
     <div class="flex h-full w-full flex-1 flex-col gap-4 rounded-xl">
+        @include('partials.past-due-banner')
         <div class="grid auto-rows-min gap-4 md:grid-cols-3">
             <div class="relative aspect-video overflow-hidden rounded-xl border border-neutral-200 dark:border-neutral-700">
                 <x-placeholder-pattern class="absolute inset-0 size-full stroke-gray-900/20 dark:stroke-neutral-100/20" />