feat: implement AI styling foundation and billing scope rework

app/Services/AiEditing/Providers/NullAiImageProvider.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Services\AiEditing\Providers;
+
+use App\Models\AiEditRequest;
+use App\Services\AiEditing\AiProviderResult;
+use App\Services\AiEditing\Contracts\AiImageProvider;
+
+class NullAiImageProvider implements AiImageProvider
+{
+    public function submit(AiEditRequest $request): AiProviderResult
+    {
+        return AiProviderResult::failed(
+            'provider_not_supported',
+            sprintf('The AI provider "%s" is not supported.', $request->provider)
+        );
+    }
+
+    public function poll(AiEditRequest $request, string $providerTaskId): AiProviderResult
+    {
+        return AiProviderResult::failed(
+            'provider_not_supported',
+            sprintf('The AI provider "%s" is not supported.', $request->provider)
+        );
+    }
+}