Add TODO comment for ensure_weight_tying in vision models

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

unsloth/models/vision.py

@@ -930,7 +930,7 @@ class FastBaseModel:
         task_type = TaskType.CAUSAL_LM,
         temporary_location = "_unsloth_temporary_saved_buffers",
         qat_scheme = None,
-        ensure_weight_tying = False,
+        ensure_weight_tying = False,  # [TODO] Add `ensure_weight_tying` for `modules_to_save` for vision models
         **kwargs,
     ):
         if os.environ.get("UNSLOTH_ENABLE_FULL_FINETUNING", "0") == "1":