Can't access calendar data using icalbuddy

I'm trying to use `icalBuddy` to get the current calendar event (`icalBuddy eventsNow`), but `icalBuddy` reports:

```
error: No calendars.
```

That's not correct, though, and doesn't match what I get running it from iTerm. That's probably because i'm on Mojave, and when I run it from iTerm (the first time), I'm prompted to allow iTerm to access my calendars, which I've allowed. But when I run it from `skhd`, I never get prompted, and there doesn't appear to be a way to manually add it.

Is there a trick to enabling this permission for `skhd`, which I _think_ will fix the problem?

Reproduce the difference between running `icalBuddy eventsNow` in iTerm and via `skhd` on Mojave, noting the permission prompt behavior. Trace the skhd command-launch path and macOS calendar-access requirements; done means identifying a supported way for skhd-launched commands to access calendars or documenting that none exists.

Written by the indexing model from the issue text.