UI - make label chooser styling more flexible

[jacobshandling]

Follow-up for #27019

Makes the styling of the label chooser more flexible, will allow seamless merging of incoming changes

• Manual QA for all new/changed functionality

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.99%. Comparing base (b91e8eb) to head (0cfa3fd).

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #27054   +/-   ##
=======================================
  Coverage   63.99%   63.99%           
=======================================
  Files        1706     1706           
  Lines      162934   162934           
  Branches     4310     4363   +53     
=======================================
  Hits       104273   104273           
  Misses      50536    50536           
  Partials     8125     8125           

Flag	Coverage Δ
frontend	54.59% <ø> (ø)

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