Instrument libakgl in opt-in coverage builds, use CTest fixtures to reset counters and emit Cobertura XML and detailed HTML reports, and upload those reports from Gitea CI. Document the local coverage workflow for contributors.
Co-authored-by: Codex (GPT-5) <noreply@openai.com>
Port the scratch-copy mutation runner used by libakerror and libakstdlib, covering libakgl source files with sampling, thresholds, JUnit reports, and test timeouts. Add a CMake target and documentation, preserve the intentionally failing character test exclusion, and migrate the sprite test to the renderer backend so mutation baselines are green.
Co-authored-by: Codex (GPT-5) <noreply@openai.com>