.Net: Bug: OnIntermediateMessage is invoked after streaming completes for AzureAIAgent, OpenAIAssistant and OpenAIResponseAgent

[westey-m]

Describe the bug
OnIntermediateMessage is getting invoked with intermediate messages only after streaming completes for AzureAIAgent, OpenAIAssistant and OpenAIResponseAgent.

To Reproduce
Observe the output from an agent when invoking in streaming mode.
The text result is streamed as individual updates, but OnIntermediateMessage is only invoked with the tool calls and full messages after the result is streamed.

Expected behavior
Messages are passed to OnIntermediateMessage as soon as they are availble.