fix: Updating ToolCall.arguments to allow for json strings that can be decoded on client side (#1685)

### What does this PR do?

Currently, `ToolCall.arguments` is a `Dict[str, RecursiveType]`.
However, on the client SDK side -- the `RecursiveType` gets deserialized
into a number ( both int and float get collapsed ) and hence when params
are `int` they get converted to float which might break client side
tools that might be doing type checking.

Closes: https://github.com/meta-llama/llama-stack/issues/1683

### Test Plan
Stainless changes --
https://github.com/meta-llama/llama-stack-client-python/pull/204
```
pytest -s -v --stack-config=fireworks tests/integration/agents/test_agents.py  --text-model meta-llama/Llama-3.1-8B-Instruct
```

llama_stack/providers/utils/inference/openai_compat.py

@@ -529,7 +529,11 @@ async def convert_message_to_openai_dict_new(
     ) -> Union[str, Iterable[OpenAIChatCompletionContentPartParam]]:
         async def impl(
             content_: InterleavedContent,
-        ) -> Union[str, OpenAIChatCompletionContentPartParam, List[OpenAIChatCompletionContentPartParam]]:
+        ) -> Union[
+            str,
+            OpenAIChatCompletionContentPartParam,
+            List[OpenAIChatCompletionContentPartParam],
+        ]:
             # Llama Stack and OpenAI spec match for str and text input
             if isinstance(content_, str):
                 return content_
@@ -570,7 +574,7 @@ async def convert_message_to_openai_dict_new(
                 OpenAIChatCompletionMessageToolCall(
                     id=tool.call_id,
                     function=OpenAIFunction(
-                        name=tool.tool_name if not isinstance(tool.tool_name, BuiltinTool) else tool.tool_name.value,
+                        name=(tool.tool_name if not isinstance(tool.tool_name, BuiltinTool) else tool.tool_name.value),
                         arguments=json.dumps(tool.arguments),
                     ),
                     type="function",
@@ -609,6 +613,7 @@ def convert_tool_call(
             call_id=tool_call.id,
             tool_name=tool_call.function.name,
             arguments=json.loads(tool_call.function.arguments),
+            arguments_json=tool_call.function.arguments,
         )
     except Exception:
         return UnparseableToolCall(
@@ -759,6 +764,7 @@ def _convert_openai_tool_calls(
             call_id=call.id,
             tool_name=call.function.name,
             arguments=json.loads(call.function.arguments),
+            arguments_json=call.function.arguments,
         )
         for call in tool_calls
     ]
@@ -890,7 +896,8 @@ async def convert_openai_chat_completion_stream(
             # ChatCompletionResponseEvent only supports one per stream
             if len(choice.delta.tool_calls) > 1:
                 warnings.warn(
-                    "multiple tool calls found in a single delta, using the first, ignoring the rest", stacklevel=2
+                    "multiple tool calls found in a single delta, using the first, ignoring the rest",
+                    stacklevel=2,
                 )
 
             if not enable_incremental_tool_calls:
@@ -971,6 +978,7 @@ async def convert_openai_chat_completion_stream(
                     call_id=buffer["call_id"],
                     tool_name=buffer["name"],
                     arguments=arguments,
+                    arguments_json=buffer["arguments"],
                 )
                 yield ChatCompletionResponseStreamChunk(
                     event=ChatCompletionResponseEvent(