Fix strict level setting for Kimi K2 tool calls when not explicitly set (#13077)

Signed-off-by: Xinyuan Tong <xinyuantong.cs@gmail.com>

python/sglang/srt/server_args.py

@@ -1728,7 +1728,10 @@ class ServerArgs:
             "1" if self.enable_deterministic_inference else "0"
         )
         # Set the highest strict level for Kimi K2 tool calls
-        if self.tool_call_parser == "kimi_k2":
+        if (
+            self.tool_call_parser == "kimi_k2"
+            and not envs.SGLANG_TOOL_STRICT_LEVEL.is_set()
+        ):
             envs.SGLANG_TOOL_STRICT_LEVEL.set(ToolStrictLevel.PARAMETER)
 
     def _handle_cache_compatibility(self):