Many of the files I checked have a 2-BSD clause stamped at the top, but I don’t know what the resulting combination of the project plus its dependencies becomes.
It is 2-BSD, will be added to the repo in a future update.
Source: asked them.
That's what I was wondering too, I have sent them an email.
Update: It's BSD 2-Clause. This will be added to the repo soon. Also the people behind it are super helpful and passionate behind the project!!