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/Cms/ValueObjects/BlockIdTest.php

@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Domain\Cms\ValueObjects\BlockId;
+
+describe('BlockId', function () {
+    it('can be created from valid string', function () {
+        $blockId = BlockId::fromString('hero-1');
+
+        expect($blockId->toString())->toBe('hero-1');
+        expect((string) $blockId)->toBe('hero-1');
+    });
+
+    it('accepts lowercase letters, numbers, hyphens, and underscores', function () {
+        $validIds = ['block-1', 'text_block', 'image123', 'my-block-id'];
+
+        foreach ($validIds as $id) {
+            $blockId = BlockId::fromString($id);
+            expect($blockId->toString())->toBe($id);
+        }
+    });
+
+    it('can generate unique block IDs', function () {
+        $blockId1 = BlockId::generate('hero');
+        $blockId2 = BlockId::generate('hero');
+
+        expect($blockId1->toString())->toStartWith('hero_');
+        expect($blockId2->toString())->toStartWith('hero_');
+        expect($blockId1->toString())->not->toBe($blockId2->toString());
+    });
+
+    it('generates block IDs with custom prefix', function () {
+        $blockId = BlockId::generate('custom');
+
+        expect($blockId->toString())->toStartWith('custom_');
+    });
+
+    it('throws exception for empty string', function () {
+        expect(fn () => BlockId::fromString(''))
+            ->toThrow(InvalidArgumentException::class, 'Block ID cannot be empty');
+    });
+
+    it('throws exception for uppercase letters', function () {
+        expect(fn () => BlockId::fromString('Block-1'))
+            ->toThrow(InvalidArgumentException::class, 'Block ID must contain only lowercase letters, numbers, hyphens, and underscores');
+    });
+
+    it('throws exception for special characters', function () {
+        expect(fn () => BlockId::fromString('block@1'))
+            ->toThrow(InvalidArgumentException::class);
+    });
+
+    it('throws exception for block ID exceeding 100 characters', function () {
+        $longId = str_repeat('a', 101);
+        expect(fn () => BlockId::fromString($longId))
+            ->toThrow(InvalidArgumentException::class, 'Block ID cannot exceed 100 characters');
+    });
+
+    it('can compare two BlockIds for equality', function () {
+        $id1 = BlockId::fromString('block-1');
+        $id2 = BlockId::fromString('block-1');
+        $id3 = BlockId::fromString('block-2');
+
+        expect($id1->equals($id2))->toBeTrue();
+        expect($id1->equals($id3))->toBeFalse();
+    });
+});
+