chore(tests): preserve generated C++ sources for CI artifacts
- Remove copilot instructions file that was causing confusion
- Add logic to copy generated .cc and .h files when PHPT tests fail
- Set up TYPEPHP_PHPT_GENERATED_ARTIFACT_DIR environment variable in CI
- Include generated source files in uploaded artifacts for debugging
- Replace curl extension with embed extension in workflow configuration
- Remove explicit PHP embed library installation from CI steps
- Update PHPT runner to use bootstrap compiler via --compiler flag
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韩天峰
2d14c9e432