fix: Set api usage billing to 100k

[zachaysan]

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Changes

1. Set up billing to 100k from 1000 from the Chargebee add-on code.
2. Fix a horrible bug that would have allowed customers to be billed multiple times for the same API calls.

How did you test this code?

Updated tests and added for codecov.

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Name	Status	Preview	Comments	Updated (UTC)
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.42%. Comparing base (16d1dda) to head (cefeb42).
Report is 15 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3996      +/-   ##
==========================================
+ Coverage   96.21%   96.42%   +0.20%     
==========================================
  Files        1142     1145       +3     
  Lines       36724    37330     +606     
==========================================
+ Hits        35335    35994     +659     
+ Misses       1389     1336      -53     

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[github-actions]

Uffizzi Preview deployment-52086 was deleted.

[matthewelwell]

Added a couple of minor comments.

[matthewelwell]

I'm approving here, but I'm not sure what's going on with the codecov workflow that seems stuck..