feat: Identity overrides in environment document

[khvn26]

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• [ ] I have added information to docs/ if required so people know about the feature!
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Changes

This PR adds identity overrides to the environment document response for local evaluation.

How did you test this code?

Added a unit test for the new mapper.

Contributes to #1762.

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Name	Status	Preview	Comments	Updated (UTC)
docs	🛑 Canceled (Inspect)			May 14, 2024 5:42pm
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Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 95.99%. Comparing base (97df705) to head (2899fd1). Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3766   +/-   ##
=======================================
  Coverage   95.99%   95.99%           
=======================================
  Files        1135     1138    +3     
  Lines       36204    36245   +41     
=======================================
+ Hits        34754    34795   +41     
  Misses       1450     1450           

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