feat: support Claude 4 Interleaved thinking (beta) (#164)

src/api/models/bedrock.py

@@ -567,6 +567,10 @@ class BedrockModel(BaseChatModel):
                     assert "function" in chat_request.tool_choice
                     tool_config["toolChoice"] = {"tool": {"name": chat_request.tool_choice["function"].get("name", "")}}
             args["toolConfig"] = tool_config
+        # add Additional fields to enable extend thinking
+        if chat_request.extra_body:
+            # reasoning_config will not be used 
+            args["additionalModelRequestFields"] = chat_request.extra_body
         return args
 
     def _create_response(

src/api/schema.py

@@ -107,6 +107,7 @@ class ChatRequest(BaseModel):
     tools: list[Tool] | None = None
     tool_choice: str | object = "auto"
     stop: list[str] | str | None = None
+    extra_body: dict | None = None
 
 
 class Usage(BaseModel):