Python: Yield FunctionResultContent in streaming chat completion path. Update tests.

[moonbox3]

Motivation and Context

Currently, if using SK's Python streaming chat completion path, we only yield the following content types: StreamingChatMessageContent and FunctionCallContent. We are not yielding FunctionResultContent which is valuable for some use cases.

Description

This PR updates the code to yield FunctionResultContent if it exists in the streaming chat completion path. When we merge the function call result content together into a StreamingChatMessageContent type, we check if that message has items (which are of type FunctionResultContent) and if so, we yield them. The filter path still works because once they're yielded, we break out of the function calling loop.

We need to include the ai_model_id if it exists for the current PromptExecutionSettings because if performing a reduce operation to add two streaming chat message chunks together, the StreamingChatMessageContent that has the function results will break if the ai_model_id is not set (the error is thrown in the __add__ override for the StreamingChatMessageContent.

Some unit tests that cover function calling were also updated -- during the test, the test JSON function args were breaking in the json.loads call because they contained single quotes and not double. We're now sanitizing the args, just in case, so we don't break there.

This PR fixes:

• Python: history is not extended with tool call related messages automatically #9408
• How to return the result of function calling execution to the front end #9968

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the SK Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
semantic_kernel
kernel.py	202	47	77%	143, 154, 158, 308–311, 423, 437–480
semantic_kernel/connectors/ai
chat_completion_client_base.py	127	2	98%	401, 411
semantic_kernel/contents
function_call_content.py	101	2	98%	186, 214
semantic_kernel/functions
kernel_function_from_prompt.py	154	7	95%	167–168, 182, 203, 221, 241, 324
TOTAL	16775	1849	89%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
2966	4 💤	0 ❌	0 🔥	1m 17s ⏱️