fix(gemini): update caching and structured request handling (#426)

Author: pushpak1300

src/Providers/Gemini/Handlers/Structured.php

@@ -110,6 +110,7 @@ protected function addStep(array $data, Request $request): void
                     promptTokens: data_get($data, 'usageMetadata.promptTokenCount', 0),
                     completionTokens: data_get($data, 'usageMetadata.candidatesTokenCount', 0),
                     thoughtTokens: data_get($data, 'usageMetadata.thoughtsTokenCount', null),
+                    cacheReadInputTokens: data_get($data, 'usageMetadata.cachedContentTokenCount', null),
                 ),
                 meta: new Meta(
                     id: data_get($data, 'id', ''),

tests/Providers/Gemini/GeminiStructuredTest.php

@@ -109,10 +109,10 @@
         ]))
         ->withProviderOptions(['cachedContentName' => $object->name])
         ->withPrompt('Summarise this document using the properties and descriptions defined in the schema.')
-        ->generate();
+        ->asStructured();
 
     Http::assertSentInOrder([
-        fn (Request $request): bool => true,
+        fn (Request $request): bool => $request->url() == 'https://generativelanguage.googleapis.com/v1beta/cachedContents',
         fn (Request $request): bool => $request->data()['cachedContent'] === $object->name,
     ]);
 
@@ -123,6 +123,7 @@
         'article_count',
     ]);
 
+    expect($response->usage->cacheReadInputTokens)->toBe(88759);
     expect($response->structured['article_count'])->toBe(358);
     expect($response->structured['legal_jurisdiction'])->toBe('European Union');
     expect($response->structured['legislation_type'])->toBe('Treaty');