Add M3 error pages and the Markdown mail theme

Error pages for 401 to 503 in an error-view root appended to view.paths,
with an inline fallback when the Vite build is missing, and a mail theme
rendered from the application's scheme JSON, with opt-in header and
message components. Completes Phase 9.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V9NnLxnPp8vaaurb3Z1MFy

tests/Feature/ServiceProviderTest.php

@@ -2,6 +2,8 @@
 
 use Illuminate\Support\Collection;
 use Illuminate\Support\Facades\Blade;
+use Illuminate\Support\Facades\File;
+use Illuminate\Support\ServiceProvider;
 use NoNameWeb\LivewireMaterial\LivewireMaterialServiceProvider;
 
 /**
@@ -35,3 +37,19 @@ it('registers the components under a configured prefix', function () {
 it('keeps blade-icons from registering an <x-icon> that would shadow ours', function () {
     expect(Blade::getClassComponentAliases())->not->toHaveKey('icon');
 });
+
+it('publishes the error pages into the application\'s errors folder', function () {
+    expect(ServiceProvider::pathsToPublish(LivewireMaterialServiceProvider::class, 'livewire-material-errors'))->toBe([
+        LivewireMaterialServiceProvider::errorViewPath().'/errors' => resource_path('views/errors'),
+    ]);
+});
+
+it('publishes the mail components where Laravel looks for them', function () {
+    expect(ServiceProvider::pathsToPublish(LivewireMaterialServiceProvider::class, 'livewire-material-mail'))->toBe([
+        LivewireMaterialServiceProvider::mailComponentPath().'/html' => resource_path('views/vendor/mail/html'),
+        LivewireMaterialServiceProvider::mailComponentPath().'/text' => resource_path('views/vendor/mail/text'),
+    ])->and(config('mail.markdown.paths'))->toContain(resource_path('views/vendor/mail'));
+
+    expect(File::files(LivewireMaterialServiceProvider::mailComponentPath().'/html'))->not->toBeEmpty()
+        ->and(File::files(LivewireMaterialServiceProvider::mailComponentPath().'/text'))->not->toBeEmpty();
+});