Update conversation ID in copilot studio client when start_conversation is called

[dineshkumar31]

Fix ### Details

1. Capture x-ms-conversationid from the start-conversation HTTP response when status is 200.
2. Persist it to _current_conversation_id so all later ask_question calls target the correct conversation

[Copilot]

Pull Request Overview

This PR fixes a bug where the conversation ID was not being persisted after starting a new conversation. The fix captures the x-ms-conversationid header from successful HTTP responses and stores it in _current_conversation_id to ensure subsequent ask_question calls target the correct conversation.

Key Changes:

• Added logic to extract and persist the conversation ID from response headers after successful API calls

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[dineshkumar31]

This pull request fixes this issue - #194

[rodrigobr-msft]

Could you run black (our formatter)? All you need to do is:

black ./libraries

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

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