fix: ignore stop key in vllm sampling params (#3879)

Signed-off-by: Ryan Lempka <rlempka@nvidia.com>

components/src/dynamo/vllm/handlers.py

@@ -44,6 +44,9 @@ def build_sampling_params(
     # Apply stop_conditions
     for key, value in request["stop_conditions"].items():
         if value is not None and hasattr(sampling_params, key):
+            # Do not add stop key to sampling params - dynamo handles stop conditions directly
+            if key == "stop":
+                continue
             setattr(sampling_params, key, value)
 
     return sampling_params