tests: add a feature diff test view and select by regex in feature tagging dashboard

[maykathm]

This adds:

• the ability to calculate the difference in feature coverage between a set of systems and a single system
• a test-based overview in the difference between test coverage

New regex

When calculating the difference between test coverage, one can now specify a regex to select a set of systems. The regex permits users to examine the missing coverage of a single system against a set of systems.

For example, now if I wish to see what features are tested in all uc versions but not uc26, I can make the following query:

New test view in feature coverage difference

This adds a new test table when looking at feature coverage difference. It shows, of the feature coverage gap, what tests contain those missing features. Each entry in the table reports only missing features that test contains (not features in general that test may have). It allows a user to quickly see where to get the biggest gains in closing the feature coverage gap.

Additionally, a user may click on an individual entry in the new test table and see what features they can gain through that test.

[github-actions]

Wed Mar 18 08:33:47 UTC 2026

Spread tests skipped

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (master@bfa385c). Learn more about missing BASE report.
⚠️ Report is 264 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##             master   #16779   +/-   ##
=========================================
  Coverage          ?   77.63%           
=========================================
  Files             ?     1351           
  Lines             ?   188169           
  Branches          ?     2446           
=========================================
  Hits              ?   146078           
  Misses            ?    33268           
  Partials          ?     8823           

Flag	Coverage Δ
unittests	77.63% <ø> (?)

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[sergiocazzolato]

Nice, lets see how it works