feat(cms,asset): add comprehensive test suite and finalize modules

- Add comprehensive test suite for CMS and Asset modules using Pest Framework
- Implement ContentTypeService::delete() protection against deletion of in-use content types
- Add CannotDeleteContentTypeInUseException for better error handling
- Fix DerivatPipelineRegistry::getAllPipelines() to handle object uniqueness correctly
- Fix VariantName::getScale() to correctly parse scales with file extensions
- Update CMS module documentation with new features, exceptions, and test coverage
- Add CmsTestHelpers and AssetTestHelpers for test data factories
- Fix BlockTypeRegistry to be immutable after construction
- Update ContentTypeService to check for associated content before deletion
- Improve BlockRendererRegistry initialization

Test coverage:
- Value Objects: All CMS and Asset value objects
- Services: ContentService, ContentTypeService, SlugGenerator, BlockValidator, ContentLocalizationService, AssetService, DeduplicationService, MetadataExtractor
- Repositories: All database repositories with mocked connections
- Rendering: Block renderers and ContentRenderer
- Controllers: API endpoints for both modules

254 tests passing, 38 remaining (mostly image processing pipeline tests)

tests/Unit/Domain/Asset/ValueObjects/ObjectKeyGeneratorTest.php

@@ -0,0 +1,92 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Domain\Asset\ValueObjects\AssetId;
+use App\Domain\Asset\ValueObjects\ObjectKeyGenerator;
+use App\Domain\Asset\ValueObjects\VariantName;
+use App\Framework\DateTime\SystemClock;
+use App\Framework\Storage\ValueObjects\ObjectKey;
+
+describe('ObjectKeyGenerator', function () {
+    it('generates key for original asset', function () {
+        $clock = new SystemClock();
+        $assetId = AssetId::generate($clock);
+        $now = new \DateTimeImmutable();
+
+        $key = ObjectKeyGenerator::generateKey($assetId, 'jpg');
+
+        expect($key)->toBeInstanceOf(ObjectKey::class);
+        expect($key->toString())->toContain('orig');
+        expect($key->toString())->toContain($now->format('Y'));
+        expect($key->toString())->toContain($now->format('m'));
+        expect($key->toString())->toContain($now->format('d'));
+        expect($key->toString())->toContain($assetId->toString());
+        expect($key->toString())->toEndWith('.jpg');
+    });
+
+    it('generates key with custom prefix', function () {
+        $clock = new SystemClock();
+        $assetId = AssetId::generate($clock);
+
+        $key = ObjectKeyGenerator::generateKey($assetId, 'png', 'custom');
+
+        expect($key->toString())->toStartWith('custom/');
+    });
+
+    it('removes leading dot from extension', function () {
+        $clock = new SystemClock();
+        $assetId = AssetId::generate($clock);
+
+        $key1 = ObjectKeyGenerator::generateKey($assetId, '.jpg');
+        $key2 = ObjectKeyGenerator::generateKey($assetId, 'jpg');
+
+        expect($key1->toString())->toBe($key2->toString());
+    });
+
+    it('generates variant key', function () {
+        $clock = new SystemClock();
+        $assetId = AssetId::generate($clock);
+        $variant = VariantName::fromString('1200w.webp');
+        $now = new \DateTimeImmutable();
+
+        $key = ObjectKeyGenerator::generateVariantKey($assetId, $variant);
+
+        expect($key)->toBeInstanceOf(ObjectKey::class);
+        expect($key->toString())->toContain('variants');
+        expect($key->toString())->toContain($now->format('Y'));
+        expect($key->toString())->toContain($now->format('m'));
+        expect($key->toString())->toContain($now->format('d'));
+        expect($key->toString())->toContain($assetId->toString());
+        expect($key->toString())->toEndWith('/1200w.webp');
+    });
+
+    it('generates variant key with custom prefix', function () {
+        $clock = new SystemClock();
+        $assetId = AssetId::generate($clock);
+        $variant = VariantName::fromString('thumb@1x');
+
+        $key = ObjectKeyGenerator::generateVariantKey($assetId, $variant, 'custom-variants');
+
+        expect($key->toString())->toStartWith('custom-variants/');
+    });
+
+    it('generates keys with date-based structure', function () {
+        $clock = new SystemClock();
+        $assetId = AssetId::generate($clock);
+        $now = new \DateTimeImmutable();
+
+        $key = ObjectKeyGenerator::generateKey($assetId, 'jpg');
+
+        $expectedPattern = sprintf(
+            '/^orig\/%s\/%s\/%s\/%s\.jpg$/',
+            $now->format('Y'),
+            $now->format('m'),
+            $now->format('d'),
+            preg_quote($assetId->toString(), '/')
+        );
+
+        expect($key->toString())->toMatch($expectedPattern);
+    });
+});
+