Support for the PHPUnit dialect of JUnit

Refactor PHPUnit support into separate phpunit-junit parser

Instead of modifying the Java JUnit parser, this creates a dedicated
PHPUnit parser that properly handles PHPUnit's nested testsuite elements.
This keeps the parsers cleanly separated and allows for future PHPUnit-
specific features.

Co-Authored-By: Matteo Beccati <matteo@beccati.com>
Co-Authored-By: Claude Code <noreply@anthropic.com>

README.md

@@ -20,6 +20,7 @@ This [Github Action](https://github.com/features/actions) displays test results
 - Java / [JUnit](https://junit.org/)
 - JavaScript / [JEST](https://jestjs.io/) / [Mocha](https://mochajs.org/)
 - Python / [pytest](https://docs.pytest.org/en/stable/) / [unittest](https://docs.python.org/3/library/unittest.html)
+- PHP / [PHPUnit](https://phpunit.de/)
 - Ruby / [RSpec](https://rspec.info/)
 - Swift / xUnit
 
@@ -147,6 +148,7 @@ jobs:
     #   java-junit
     #   jest-junit
     #   mocha-json
+    #   phpunit-junit
     #   python-xunit
     #   rspec-json
     #   swift-xunit
@@ -314,6 +316,14 @@ This is due to the fact Java stack traces don't contain a full path to the sourc
 Some heuristic was necessary to figure out the mapping between the line in the stack trace and an actual source file.
 </details>
 
+<details>
+  <summary>phpunit-junit</summary>
+
+[PHPUnit](https://phpunit.de/) can generate JUnit XML via CLI:
+`phpunit --log-junit reports/phpunit-junit.xml`
+
+</details>
+
 <details>
   <summary>jest-junit</summary>