feat: Mutation Testing

[fpbgg]

Description

This is my first swing at introducing mutation tests to our GitHub Actions workflows.

Mutation testing is a methodology where you mutate your source code and measure how many mutants "survive" your test suites. This provides a useful measurement for the quality of your test suite.

To run these tests locally:

1. cargo install cargo-mutagen
2. cargo mutagen

(Currently there's a missing file error, but the test cases are run and evaluated in target/mutagen/mutations so I'm assuming it's a coverage file issue.)

Additional info (benefits, drawbacks, caveats)

Checklist

• Test coverage for new or modified code paths
• Changelog is updated
• Required documentation changes (e.g., docs/rpc/openapi.yaml and rpc-endpoints.md for v2 endpoints, event-dispatcher.md for new events)
• New clarity functions have corresponding PR in clarity-benchmarking repo
• New integration test(s) added to bitcoin-tests.yml

[codecov]

Codecov Report

Merging #3806 (f1749ce) into develop (cec7b4b) will decrease coverage by 26.31%.
Report is 18 commits behind head on develop.
The diff coverage is n/a.

❗ Current head f1749ce differs from pull request most recent head 3b7b25e. Consider uploading reports for the commit 3b7b25e to get more accurate results

@@             Coverage Diff              @@
##           develop    #3806       +/-   ##
============================================
- Coverage    84.62%   58.31%   -26.31%     
============================================
  Files          302        1      -301     
  Lines       286798      571   -286227     
============================================
- Hits        242699      333   -242366     
+ Misses       44099      238    -43861     

see 301 files with indirect coverage changes

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[saralab]

@KeewenawSTX Is this something you can own ? Mutation Testing is worth investing in.

[CLAassistant]

All committers have signed the CLA.

[saralab]

Alin has a new PR , closing this