Fix: Patch LiteLLM (#9416)

### What problem does this PR solve?

Patch LiteLLM refactor. #9408

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

rag/llm/chat_model.py

@@ -1455,7 +1455,7 @@ class LiteLLMBase(ABC):
         if self.model_name.lower().find("qwen3") >= 0:
             kwargs["extra_body"] = {"enable_thinking": False}
 
-        completion_args = self._construct_completion_args(history=history, **gen_conf)
+        completion_args = self._construct_completion_args(history=history, stream=False, tools=False, **gen_conf)
         response = litellm.completion(
             **completion_args,
             drop_params=True,
@@ -1475,7 +1475,7 @@ class LiteLLMBase(ABC):
         logging.info("[HISTORY STREAMLY]" + json.dumps(history, ensure_ascii=False, indent=4))
         reasoning_start = False
 
-        completion_args = self._construct_completion_args(history=history, **gen_conf)
+        completion_args = self._construct_completion_args(history=history, stream=True, tools=False, **gen_conf)
         stop = kwargs.get("stop")
         if stop:
             completion_args["stop"] = stop
@@ -1571,17 +1571,27 @@ class LiteLLMBase(ABC):
         self.toolcall_session = toolcall_session
         self.tools = tools
 
-    def _construct_completion_args(self, history, **kwargs):
+    def _construct_completion_args(self, history, stream: bool, tools: bool, **kwargs):
         completion_args = {
             "model": self.model_name,
             "messages": history,
-            "stream": False,
-            "tools": self.tools,
-            "tool_choice": "auto",
             "api_key": self.api_key,
             **kwargs,
         }
-        if self.provider in SupportedLiteLLMProvider:
+        if stream:
+            completion_args.update(
+                {
+                    "stream": stream,
+                }
+            )
+        if tools and self.tools:
+            completion_args.update(
+                {
+                    "tools": self.tools,
+                    "tool_choice": "auto",
+                }
+            )
+        if self.provider in FACTORY_DEFAULT_BASE_URL:
             completion_args.update({"api_base": self.base_url})
         elif self.provider == SupportedLiteLLMProvider.Bedrock:
             completion_args.pop("api_key", None)
@@ -1611,7 +1621,7 @@ class LiteLLMBase(ABC):
                 for _ in range(self.max_rounds + 1):
                     logging.info(f"{self.tools=}")
 
-                    completion_args = self._construct_completion_args(history=history, **gen_conf)
+                    completion_args = self._construct_completion_args(history=history, stream=False, tools=True, **gen_conf)
                     response = litellm.completion(
                         **completion_args,
                         drop_params=True,
@@ -1708,7 +1718,7 @@ class LiteLLMBase(ABC):
                     reasoning_start = False
                     logging.info(f"{tools=}")
 
-                    completion_args = self._construct_completion_args(history=history, **gen_conf)
+                    completion_args = self._construct_completion_args(history=history, stream=True, tools=True, **gen_conf)
                     response = litellm.completion(
                         **completion_args,
                         drop_params=True,
@@ -1786,7 +1796,7 @@ class LiteLLMBase(ABC):
                 logging.warning(f"Exceed max rounds: {self.max_rounds}")
                 history.append({"role": "user", "content": f"Exceed max rounds: {self.max_rounds}"})
 
-                completion_args = self._construct_completion_args(history=history, **gen_conf)
+                completion_args = self._construct_completion_args(history=history, stream=True, tools=True, **gen_conf)
                 response = litellm.completion(
                     **completion_args,
                     drop_params=True,