Throw UnreachableException for ambiguous shortnames in Production

[knuhau]

Problem

When an organization has multiple shortnames in Ressursregisteret and the org claim is missing from the token, the system cannot determine the correct mapping. We need to prevent this ambiguity from causing silent failures in production.

Proposed Solution

Update the transmission logic to handle multiple shortnames based on the environment:

Production: Throw an UnreachableException if a 1:1 mapping cannot be resolved. This ensures we maintain data integrity and get notified of the issue.

Test/Development (e.g., TT02): Retain current behavior (warning)