Bug: Disallow user to check NCA / Outputs tabs without mapping data

[Gero1999]

Description

When user has not mapped the data (define column names and accepted) it should not be able to go through other tabs (NCA or Outputs) as it can be confusing for them to see errror messages afterwards. Instead, those tabs should remain disable and perhpaps even show a notification

To reproduce

Intiiate the app and click NCA or Outputs tab. In the second one you won't find results but instead just error messages.

Expected behaviour

Disability to go to Ouptuts or NCA without mapping.
Notification with instructions on what to do (mapping the data)