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 79.18%. Comparing base (db056df) to head (2c2e95f).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@ Coverage Diff @@## master #456 +/- ##
==========================================
+ Coverage 78.76% 79.18% +0.41% 
==========================================
Files 7 7 Lines 1851 1869 +18 ==========================================
+ Hits 1458 1480 +22 + Misses 393 389 -4 

Flag	Coverage Δ
Linux	79.18% <100.00%> (+0.41%)	⬆️
Python-3.10	79.02% <100.00%> (+0.31%)	⬆️
Python-3.11	79.13% <100.00%> (+0.41%)	⬆️
Python-3.13	79.02% <100.00%> (+0.31%)	⬆️
Python-3.9	79.01% <100.00%> (+0.31%)	⬆️
Windows	79.13% <100.00%> (+0.28%)	⬆️
macOS	79.07% <100.00%> (+0.31%)	⬆️

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