`vr` return `0` when no scripts are available

[ayakovlenko]

vr return 0 when no scripts are available:

$ vr run blah
warn: No scripts available.
See https://velociraptor.run for guidance on how to create scripts.

echo $?
0

Must return a non-zero exit code.

Happens both when either of scripts.(yaml|json|ts) is missing or when a command itself is missing:

$ vr run blah
error: Script blah not found
Run vr without arguments to see a list of available scripts.

$ echo $?
0