Checklist

Please mark these items with an [x]

• I've already searched through existing tickets
• Other people will find this feature useful

Feature Description

In v4 both ResourceFunc and ResourceInput were exported and users could depend on these types. In v5 it seems that these two types didn't make it to the export list. A good reason for also exporting would be symmetry: EventSourceInput and EventSourceFunc are exported so as a user I would expect the same for resources. Would you consider exporting them?

If you're ok with this, I would gladly make a PR to fullcalendar-schedule as this is a trivial change.