Add hook for permission prompt

[raine]

Describe the feature or problem you'd like to solve

In Claude Code, you have specific hook that fires when user is prompted for a permission, https://code.claude.com/docs/en/hooks#notification

Proposed solution

Add a similar hook to Copilot CLI. This will allow creating integrations that notify user when Copilot is asking for users permission to run some tool etc.

Example prompts or workflows

I want to support Copilot CLI in a tool, and the use case is that user is notified if Copilot CLI is waiting for user input. With the current hook setup, this does not appear possible.

Additional context

No response

[huntj88]

I also needed this behavior. This is possible with --acp if you need a workaround