Improve mutation tests (#135)

[rekmixa]

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	❌
Fixed issues	#135

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.33%. Comparing base (8d62394) to head (645b609).

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #136      +/-   ##
============================================
- Coverage     99.33%   99.33%   -0.01%     
  Complexity      162      162              
============================================
  Files            11       11              
  Lines           452      451       -1     
============================================
- Hits            449      448       -1     
  Misses            3        3              

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[samdark]

Looks 👍 . Please add a line for CHANGELOG for additional validation added. Thanks.

[Copilot]

Pull request overview

Improves mutation testing robustness by adding/adjusting tests and tightening validation in the logging context provider.

Changes:

• Added validation to reject negative $traceLevel in SystemContextProvider and updated related documentation.
• Expanded PHPUnit coverage for invalid/unsupported log levels and trace collection expectations.
• Updated Infection configuration to ignore mutations involving register_shutdown_function.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/ContextProvider/SystemContextProvider.php	Adds constructor validation for non-negative trace level; strengthens closure typing in trace filtering.
tests/ContextProvider/SystemContextProviderTest.php	New tests covering invalid trace level and presence of expected context keys.
tests/LoggerTest.php	Adds tests for invalid log levels; makes trace line assertion resilient to line shifts; strengthens excluded-trace-path assertions.
src/Logger.php	Refactors deprecated validateLevel() to delegate to assertLevelIsValid() and adjusts docblock.
infection.json.dist	Configures Infection to globally ignore source containing register_shutdown_function.
CHANGELOG.md	Documents the trace level validation change.

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