feat(chat): use ChatStream to show tool description

[ctlai95]

Problem

ChatStream should be able to send messages for more use cases than just bash output.

Solution

Reuse the chat stream class for all tool messages

---

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[github-actions]

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[ashishrp-aws]

nit: why is it undefined here for tool logs?

[ctlai95]

I was thinking it should be generic, not always plaintext