[Fixes #13067] Thesaurus: improve management commands

[etj]

New management command datailed in #13067

Checklist

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[codecov]

Codecov Report

Attention: Patch coverage is 11.36364% with 234 lines in your changes missing coverage. Please review.

Project coverage is 67.79%. Comparing base (8eb10ca) to head (b23581c).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #13082      +/-   ##
==========================================
- Coverage   67.80%   67.79%   -0.01%     
==========================================
  Files         977      979       +2     
  Lines       57282    57356      +74     
  Branches     6604     6621      +17     
==========================================
+ Hits        38838    38887      +49     
- Misses      16884    16908      +24     
- Partials     1560     1561       +1     

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