I'm starting the process of re-implementing our infrastructure-as-code with Pulumi and I'm seeing the different stack configuration files (dev/test etc) in my git project. The stack config files include encryption salts however, is it safe to commit these to Git?
Yep, it is. From the docs:
The thing you need to keep secret is the passphrase itself. The salt has no use without that.
https://www.pulumi.com/docs/concepts/secrets/#committing-configuration-to-source-control