Adding groups logic and restrictions (#454)

* Adding groups logic and restrictions

* Cleaning up some redundant code

* hastily made translations

* Linter issues

* More linting

* PR comments

* Covering other APIs with age filters per comment

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Co-authored-by: Robert Clabough <robert@clabough.tech>

server/prisma/models/user.prisma

@@ -22,6 +22,8 @@ model User {
     saves       SaveSlot[]
     screenshots Screenshot[]
     playtime    Playtime[]
+
+    groups UserGroup[]
 }
 
 model Notification {