App-GHGen-0.09

Changes for version 0.09 - 2026-08-10

Bug Fixes
- Fixed Detector::detect_project_type returning (undef) — a one-element list — in list context when no project type is detected. `return undef unless @detections` returns the scalar undef in list context, which Perl wraps in a list. Changed to `return unless @detections` (bare return), which correctly returns () in list context and undef in scalar context, matching the POD spec.
Enhancements
- Update to shogo82148/actions-setup-perl@v1.43.1
- Added t/mutant_killers.t: 25 subtests that kill all surviving mutants from xt/mutant_20260810_160920.t. Covers CostEstimator (estimate_savings total_minutes > 0 boundary; estimate_duration sequential-vs-parallel branch and max-accumulation comparison), Detector (file-count > 0 boundary for all 8 language detectors: perl pm, perl t, python, go, ruby, php, java, cpp), Fixer::add_caching (checkout-detection condition), Interactive::prompt_choice (marker == default; answer >= 1 and <= @choices bounds), and Reporter (generate_markdown_report and generate_github_comment savings-cost > 0). Documents the >= variant of the estimate_duration max-accumulation mutant as a semantically equivalent mutant (not distinguishable by semantic tests).
- Added t/path.t: 34 path-coverage subtests targeting execution paths not covered by existing test files. Covers Analyzer (broad-trigger scalar push, falsy push, paths-only filter, unpinned/outdated cap), Fixer (setup-node/python via uses, add_caching insertion at position 0, unrecognised project type, no-runs-on guard, trigger-filter HASH paths), CostEstimator (zero-saving branches, proportional percentage, free-tier boundary, matrix scalar value), and Detector (scalar/list context empty result, get_project_indicators all three branches).