Add unit and feature tests for ticket processing and article management

- Implement Fake repositories and services for testing purposes.
- Create tests for Article API including creation, validation, and listing.
- Develop ProcessTicketJobFlowTest to validate ticket processing logic.
- Add QuickReplyAdminTest for creating and updating quick replies.
- Implement TicketAndArticleModelTest to ensure proper cascading deletes and credential encryption.
- Create TicketIngestionTest for ticket creation and job dispatching.
- Add TicketShowPageTest to verify rendering of quick replies and tool calls.
- Implement unit tests for ClassifierPromptBuilder, EmbeddingService, LlmJsonDecoder, QuickReplyResolver, SupportReplyService, TicketResultPayloadBuilder, TicketToolCallService, and ToolCallRequestValidator.

tests/Unit/AIClassifierServiceTest.php

@@ -41,22 +41,9 @@ class AIClassifierServiceTest extends TestCase
             }
         };
 
-        $settings = new class extends AppSettingsService
-        {
-            public function getPrompt(string $key, ?string $default = null): ?string
-            {
-                return 'Select best article.';
-            }
-
-            public function get(string $key, ?string $default = null): ?string
-            {
-                return $default;
-            }
-        };
-
         $service = new AIClassifierService(
             $client,
-            $settings,
+            $this->fakeSettings(),
             new ClassifierPromptBuilder,
             new LlmJsonDecoder,
             new ToolCallRequestValidator
@@ -81,4 +68,122 @@ class AIClassifierServiceTest extends TestCase
         $this->assertStringContainsString('Allowed actions: ["domain_inf"]', $client->prompt);
         $this->assertStringContainsString('Internal note for support assistant', $client->prompt);
     }
+
+    public function test_it_falls_back_when_ranking_disabled(): void
+    {
+        config()->set('services.llm.ranking_enabled', false);
+
+        $client = new class implements LlmClientInterface
+        {
+            public function embed(string $text): array
+            {
+                return [];
+            }
+
+            public function generate(string $prompt, array $options = []): string
+            {
+                return '{}';
+            }
+        };
+
+        $service = new AIClassifierService(
+            $client,
+            $this->fakeSettings(),
+            new ClassifierPromptBuilder,
+            new LlmJsonDecoder,
+            new ToolCallRequestValidator
+        );
+
+        $result = $service->rank('vraag', [$this->candidate(15)]);
+        $this->assertSame(15, $result->articleId);
+        $this->assertSame(0.2, $result->confidence);
+    }
+
+    public function test_it_falls_back_when_llm_json_is_invalid(): void
+    {
+        config()->set('services.llm.ranking_enabled', true);
+
+        $client = new class implements LlmClientInterface
+        {
+            public function embed(string $text): array
+            {
+                return [];
+            }
+
+            public function generate(string $prompt, array $options = []): string
+            {
+                return 'not-json';
+            }
+        };
+
+        $service = new AIClassifierService(
+            $client,
+            $this->fakeSettings(),
+            new ClassifierPromptBuilder,
+            new LlmJsonDecoder,
+            new ToolCallRequestValidator
+        );
+
+        $result = $service->rank('vraag', [$this->candidate(21)]);
+        $this->assertSame(21, $result->articleId);
+        $this->assertStringContainsString('invalid JSON', $result->explanation);
+    }
+
+    public function test_it_falls_back_when_article_id_not_in_candidates(): void
+    {
+        $client = new class implements LlmClientInterface
+        {
+            public function embed(string $text): array
+            {
+                return [];
+            }
+
+            public function generate(string $prompt, array $options = []): string
+            {
+                return json_encode([
+                    'article_id' => 999,
+                    'confidence' => 0.9,
+                    'explanation' => 'x',
+                ]);
+            }
+        };
+
+        $service = new AIClassifierService(
+            $client,
+            $this->fakeSettings(),
+            new ClassifierPromptBuilder,
+            new LlmJsonDecoder,
+            new ToolCallRequestValidator
+        );
+
+        $result = $service->rank('vraag', [$this->candidate(33)]);
+        $this->assertSame(33, $result->articleId);
+        $this->assertStringContainsString('schema invalid', $result->explanation);
+    }
+
+    private function fakeSettings(): AppSettingsService
+    {
+        return new class extends AppSettingsService
+        {
+            public function getPrompt(string $key, ?string $default = null): ?string
+            {
+                return 'Select best article.';
+            }
+
+            public function get(string $key, ?string $default = null): ?string
+            {
+                return $default;
+            }
+        };
+    }
+
+    private function candidate(int $id): ArticleCandidateDTO
+    {
+        return new ArticleCandidateDTO(
+            articleId: $id,
+            title: 'A',
+            content: 'B',
+            distance: 0.2
+        );
+    }
 }