Level represents the degree of danger for a security advisory
Bun behaves differently depending on the values returned from the scan() hook:
In any case, Bun always pretty prints all the advisories, but...
→ if any fatal, Bun will immediately cancel the installation and quit with a non-zero exit code
→ else if any warn, Bun will either ask the user if they'd like to continue with the install if in a TTY environment, or immediately exit if not.