Add Open Tool (#27499)

I've seen models try to run `open` in Bash. This is a cross-platform
version of that.

<img width="634" alt="Screenshot 2025-03-26 at 10 27 40 AM"
src="https://github.com/user-attachments/assets/b18cb50f-6e2f-4770-b15c-1040916a420a"
/>

Release Notes:

- N/A
61be869352Richard Feldman committed on 3/27/2025, 10:20:59 PM· committed by GitHubparent7537f05
6 files changedLine totals unavailable