[ perf ] Replace json-> orjson in hot path (#11221)

Signed-off-by: vincentzed <207368749+vincentzed@users.noreply.github.com>

python/sglang/srt/server_args.py

@@ -22,6 +22,8 @@ import random
 import tempfile
 from typing import Dict, List, Literal, Optional, Union
 
+import orjson
+
 from sglang.srt.connector import ConnectorType
 from sglang.srt.function_call.function_call_parser import FunctionCallParser
 from sglang.srt.lora.lora_registry import LoRARef
@@ -3041,7 +3043,7 @@ class ServerArgs:
             self.model_path,
             trust_remote_code=self.trust_remote_code,
             revision=self.revision,
-            model_override_args=json.loads(self.json_model_override_args),
+            model_override_args=orjson.loads(self.json_model_override_args),
             **kwargs,
         )
         return hf_config