feat: add backstage/filament-mails

resources/views/vendor/filament-mails/mails/download.blade.php

@@ -0,0 +1,8 @@
+<a type="button"
+    href="{{ route('filament.' . Filament\Facades\Filament::getCurrentPanel()->getId() . '.mails.attachment.download', [
+        'tenant' => Filament\Facades\Filament::getTenant(),
+        'mail' => $getState()->mail_id,
+        'attachment' => $getState()->id,
+        'filename' => $getState()->filename,
+    ]) }}"
+    class="rounded-md bg-white px-3.5 py-2.5 text-sm font-semibold cursor-pointer text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 hover:bg-gray-50">Download</a>

resources/views/vendor/filament-mails/mails/html.blade.php

@@ -0,0 +1,5 @@
+<div class="prose prose-sm sm:prose lg:prose-lg xl:prose-2xl max-w-full overflow-x-auto">
+    <pre class="whitespace-pre-wrap break-words">
+        <code class="language-html">{{ $html }}</code>
+    </pre>
+</div>

resources/views/vendor/filament-mails/mails/preview.blade.php

@@ -0,0 +1,6 @@
+<div class="w-full h-screen">
+    <iframe
+        src="{{ route('filament.' . Filament\Facades\Filament::getCurrentPanel()->getId() . '.mails.preview', ['tenant' => Filament\Facades\Filament::getTenant(), 'mail' => $mail->id]) }}"
+        class="w-full h-full max-w-full" style="width: 100vw; height: 100vh; border: none;">
+    </iframe>
+</div>