[Bug] Add tests for unmapped SR measurements

[fedorov]

Describe the Bug

Follow up on https://github.com/OHIF/Viewers/pull/5416#issuecomment-3371478819

Steps to Reproduce

Per @sedghi there are no tests to ensure there is no regression in support of unmapped SRs.

The current behavior

No tests.

The expected behavior

Tests are present. We should use the SR samples from the earlier issues for those tests. @igoroctaviano and I will discuss and prioritize.

System Information

n/a

[fedorov]

Note that SR panel for those shows incorrect units -"HU" for MR.

Screenshot from #5416:

[fedorov]

Also related to #5081 and #5082