test: use TrmnlPipeline::fake() to speed up test suite

tests/Feature/ImageGenerationWithoutFakeTest.php

@@ -0,0 +1,55 @@
+<?php
+
+use App\Models\Device;
+use App\Models\DeviceModel;
+use App\Services\ImageGenerationService;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+
+uses(RefreshDatabase::class);
+
+beforeEach(function (): void {
+    Storage::fake('public');
+    Storage::disk('public')->makeDirectory('/images/generated');
+});
+
+it('generates 4-color 2-bit PNG with device model', function (): void {
+    // Create a DeviceModel for 4-color, 2-bit PNG
+    $deviceModel = DeviceModel::factory()->create([
+        'width' => 800,
+        'height' => 480,
+        'colors' => 4,
+        'bit_depth' => 2,
+        'scale_factor' => 1.0,
+        'rotation' => 0,
+        'mime_type' => 'image/png',
+        'offset_x' => 0,
+        'offset_y' => 0,
+    ]);
+
+    // Create a device with the DeviceModel
+    $device = Device::factory()->create([
+        'device_model_id' => $deviceModel->id,
+    ]);
+
+    $markup = '<div style="background: white; color: black; padding: 20px;">Test Content</div>';
+    $uuid = ImageGenerationService::generateImage($markup, $device->id);
+
+    // Assert the device was updated with a new image UUID
+    $device->refresh();
+    expect($device->current_screen_image)->toBe($uuid);
+
+    // Assert PNG file was created
+    Storage::disk('public')->assertExists("/images/generated/{$uuid}.png");
+
+    // Verify the image file has content and isn't blank
+    $imagePath = Storage::disk('public')->path("/images/generated/{$uuid}.png");
+    $imageSize = filesize($imagePath);
+    expect($imageSize)->toBeGreaterThan(200); // Should be at least 200 bytes for a 2-bit PNG
+
+    // Verify it's a valid PNG file
+    $imageInfo = getimagesize($imagePath);
+    expect($imageInfo[0])->toBe(800); // Width
+    expect($imageInfo[1])->toBe(480); // Height
+    expect($imageInfo[2])->toBe(IMAGETYPE_PNG); // PNG type
+
+})->skipOnCI();