acp_thread: Respect terminal settings shell for terminal tool environment (#39349)

When sourcing the project environment for the terminal tool, we will now
do so by spawning the shell specified by the users `terminal.shell`
setting (or as usual fall back to the login shell).

Closes #37687 

Release Notes:

- N/A
bf48a95344Lukas Wirth committed on 10/2/2025, 8:10:55 PM· committed by GitHubparent7c3a21f
13 files changedLine totals unavailable