[Question] compound shortcut

Hello,

I'm trying to set up some shortcuts like this:

```
alt - c - 4 : (...)
```
Isn't this a valid "shortcut"? (alt + letter + number)If I add it, besides not working skhd starts malfunctioning too.

Thanks guy!

No source file, test, or entry point is named. Start by reproducing the `alt - c - 4` shortcut and checking the daemon's behavior when it is added; done means determining whether the compound shortcut is supported and documenting or correcting the malfunction it causes.

Written by the indexing model from the issue text.