Feat/groups-/server-validation-useEditing

[JohanHjelsethStorstad]

A big PR that contains

• The group system
• A refactor to create a separate /server directory #209
• A new way to write zod validations
• The useEditing hook #208

[Paulijuz]

I also think @theodorklauritzen should maybe have a look to confirm that nothing feide related has been broken

[JohanHjelsethStorstad]

@theodorklauritzen can merge it

[theodorklauritzen]

Things look good, but there a a few small bugs, but they are not critical.

• Delete collection button is shown on special collections
• Create user from the admin dashboard does not work

I have only tested the UI where there have been changes to the code, but it seems nice :))

[Paulijuz]

Woho! Finally