Update registry.py

Added Isaac model architecture.

Author: oscardev256

vllm/model_executor/models/registry.py

@@ -299,6 +299,7 @@
         "idefics3",
         "Idefics3ForConditionalGeneration",
     ),
+    "IsaacForConditionalGeneration": ("isaac", "IsaacForConditionalGeneration"),
     "SmolVLMForConditionalGeneration": ("smolvlm", "SmolVLMForConditionalGeneration"),  # noqa: E501
     "KeyeForConditionalGeneration": ("keye", "KeyeForConditionalGeneration"),
     "KeyeVL1_5ForConditionalGeneration": (