SG-43999: add custom entity config features

[fauverick]

This PR introduces 4 new functions that allow users to configure custom entity (previously can only be done through the UI):

• custom_entity_read: read the config of a custom entity
• custom_entity_enable: enable & set the display name/configuration flags of a custom entity
• custom_entity_update: update the display name/configuration flags of an enabled custom entity
• custom_entity_disable: disable a custom entity. Will return an error if the custom entity currently has existing records. Require passing force=True to disable anyway.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.13%. Comparing base (db056df) to head (c272359).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #456      +/-   ##
==========================================
+ Coverage   78.76%   79.13%   +0.36%     
==========================================
  Files           7        7              
  Lines        1851     1874      +23     
==========================================
+ Hits         1458     1483      +25     
+ Misses        393      391       -2     

Flag	Coverage Δ
Linux	79.13% <100.00%> (+0.36%)	⬆️
Python-3.10	79.08% <100.00%> (+0.36%)	⬆️
Python-3.11	79.08% <100.00%> (+0.36%)	⬆️
Python-3.13	79.08% <100.00%> (+0.36%)	⬆️
Python-3.9	79.07% <100.00%> (+0.36%)	⬆️
Windows	79.19% <100.00%> (+0.33%)	⬆️
macOS	79.13% <100.00%> (+0.36%)	⬆️

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