Add Calendar full access usage descriptions

[globalhuman]

Fixes #1032.

Adds the required NSCalendarsFullAccessUsageDescription privacy strings to the app and intent extension bundles so EventKit full calendar access requests can present the iOS permission prompt.

[holzschu]

I've incorporated both your PR into the experimental branch. I'm going to upload two builds on the AppStore so you can test them. If everything works, I'll incorporate things into the main branch.

By the way, I'm curious about what you will be able to make with those changes. If you can, would you share the resulting scripts or Shortcuts?

[globalhuman]

I've been using pythonista which already has support for calendar and bluetooth and this workflow works there. I am trying to co-locate all my scripts into a-shell for simplicity.

The calendar access is to read the calendars and edit a markdown todo list which places the calendar events in the todo list for that day. I will be adding write calendar support to so that when a task is complete it will create a mirrored calendar event for a consistent record of my day.

The bluetooth access is for a number of smart home things. I can connect directly to hue, tuya, etc to read device state plus also control.