feat(faq): video tutorial + full-width layout + wider grid

- New tenant setting: settings.faq_video_url. TextInput on Settings
  page → Liste configurabile (accepts YouTube watch URL, youtu.be
  short URL, YouTube shorts/embed URL, or Vimeo URL).
- Faq page has getVideoEmbedUrl() that converts recognized URLs to
  their /embed/ variant. Unknown URLs fall back to a "?" card with
  a direct link. Admins see a "configure in Settings" nudge when no
  URL is set.
- Video renders as a 16:9 iframe capped at 480px height, above the
  hero.
- .faq-shell is now width:100% (was max-width:1200px) so FAQ uses
  all available horizontal space.
- .faq-grid switched from strict 2 columns to
  repeat(auto-fit, minmax(420px, 1fr)) so wide screens get 3 columns
  and narrow screens stack.

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

app/Filament/Tenant/Pages/Faq.php

@@ -45,6 +45,35 @@ class Faq extends Page
         return Hints::AREAS;
     }
 
+    /**
+     * Convert a YouTube / Vimeo watch URL to the embed URL that goes in
+     * an <iframe src="">. Returns null if the URL is empty or the host
+     * isn't recognized (in which case we fall back to a plain link).
+     */
+    public function getVideoEmbedUrl(): ?string
+    {
+        $tenant = app(\App\Tenancy\TenantManager::class)->current();
+        $raw = trim((string) ($tenant?->settings['faq_video_url'] ?? ''));
+        if ($raw === '') return null;
+
+        // YouTube: watch?v=ID | youtu.be/ID | shorts/ID
+        if (preg_match('#(?:youtube\.com/(?:watch\?v=|shorts/|embed/)|youtu\.be/)([A-Za-z0-9_-]{6,})#', $raw, $m)) {
+            return 'https://www.youtube.com/embed/' . $m[1];
+        }
+        // Vimeo: vimeo.com/ID
+        if (preg_match('#vimeo\.com/(\d+)#', $raw, $m)) {
+            return 'https://player.vimeo.com/video/' . $m[1];
+        }
+        return null;
+    }
+
+    public function getVideoRawUrl(): ?string
+    {
+        $tenant = app(\App\Tenancy\TenantManager::class)->current();
+        $raw = trim((string) ($tenant?->settings['faq_video_url'] ?? ''));
+        return $raw !== '' ? $raw : null;
+    }
+
     public function getGrouped(): array
     {
         $q = mb_strtolower(trim($this->search));