fix(amazonq): prompt user to choose a folder in the chat for /doc

[KevinDing1]

Problem

When a user clicks the "Change folder" button when creating or updating a README, the "Generating answer..." loading text appears, even though there is no answer being generated, since we are waiting for the user to choose a folder.

This is an especially confusing UX if the user is connected to an SSH host:

Solution

When the user clicks the "Change folder" button, send a "Choose a folder to continue" message in the chat.

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[github-actions]

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