v1.4.0 — cycle CPU default

The cycle CPU backend is now the default. The former backend remains available through explicit source-build selection.

Preserves mouse aiming, crosshair and timed Zapper shots/jumping. The owner playtest passed. Adaptive widescreen is a separate follow-up, excluded from this release.

Validation covers the recorded short owner playtests and focused automated checks. Full-game completion and new Linux/macOS runtime qualification are not claimed by this Windows release.

Game archives contain no ROM or personal save data. Select the matching original ROM at first launch. Legacy binary save states require the retained legacy backend; they do not load in cycle mode. Existing cartridge battery/password progress is preserved through the documented storage/import workflow.

Source default: master at c2fe4ad8b8d03480486e1379b3f7a151a65c765d.