Rename model_class to Gemma3nConditionalGenerate

kf_config.json

@@ -2,7 +2,7 @@
   "library_name": "kerasformers",
   "kerasformers_version": "1.2.1",
   "model_module": "kerasformers.models.gemma3n",
-  "model_class": "Gemma3nForConditionalGeneration",
+  "model_class": "Gemma3nConditionalGenerate",
   "variant": "gemma-3n-e2b",
   "weights": "model.weights.h5",
   "schema_version": 2,
@@ -187,4 +187,4 @@
   "eoa_token_id": 262272,
   "audio_token_id": 262273,
   "tie_word_embeddings": true
-}
+}