Update test suite to ensure 100% code coverage

[clue]

Builds on top of #42 and clue/reactphp-eventsource#35

[Copilot]

Pull request overview

This PR adds automated 100% code coverage validation to the test suite. It builds on top of the test environment improvements from PR #42, adding both CI enforcement and documentation for the code coverage requirement.

Changes:

• Added automated coverage validation in CI workflow to fail builds if code coverage is below 100%
• Added code coverage badge to README
• Documented the code coverage requirement and how to generate coverage reports locally

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
README.md	Added code coverage badge and documentation explaining the 100% coverage requirement with instructions for generating local coverage reports
.github/workflows/ci.yml	Added clover.xml coverage report generation and PHP script to validate 100% code coverage after test runs

Comments suppressed due to low confidence (2)

.github/workflows/ci.yml:42

• The XML parsing lacks error handling. If the clover.xml file doesn't exist, is malformed, or doesn't have the expected structure, the script will fail with a PHP error instead of a clear message. Consider adding error handling to check if the file exists and if the expected XML structure is present before accessing the metrics attributes.

          $metrics = simplexml_load_file('clover.xml')->project->metrics;
          exit((int) $metrics['statements'] === (int) $metrics['coveredstatements'] ? 0 : 1);

.github/workflows/ci.yml:42

• The coverage check script doesn't provide any diagnostic output when coverage is below 100%. Consider adding an error message that shows the actual coverage percentage to help developers understand what needs to be fixed. For example, output the number of covered vs total statements before exiting.

      - name: Check 100% code coverage
        shell: php {0}
        run: |
          <?php
          $metrics = simplexml_load_file('clover.xml')->project->metrics;
          exit((int) $metrics['statements'] === (int) $metrics['coveredstatements'] ? 0 : 1);

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.