v0.4.0 — cycle CPU default

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

The compiler and frozen Windows CLI now default to cycle output, including cycle project scaffolding and required headers. Explicit --legacy and legacy configuration remain available. Shared cycle support preserves PAL timing, password/battery storage, Zapper input, modern HD Mods, four logical co-op seats, presentation hooks and returning-frame rollback netplay.

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.

The frozen CLI generated and compiled both cycle-default and explicit-legacy static libraries. Generated game source projects remain pinned to their selected dependencies. No ROM is included.

Source default: master at 62875971aea639ad461d8f3d42a4875b849b89bd.