Mandate Extremely High Coverage for Tests Module

[medley56]

Summary

We should mandate extremely high coverage threshold for the tests module. If tests aren't running or a lot of code is being skipped, that's a problem.

Implementation

Modify the codecov config to add something like this:

# Custom group for tests module with higher threshold
      tests:
        target: 99%  # Very high threshold for test files
        threshold: 1%  # Allow only 1% drop
        paths:
          - "tests/**"  # Adjust this path to match your test directory
        if_no_uploads: error
        only_pulls: false