Subsystem: Deployment Channels & Updates

Compile-time channel isolation and update mechanisms (src/deployment/).

Mutually Exclusive Channels

• Production: binary m31a, global directory ~/.local/share/m31a, feed stable.
• Development: binary m31a-dev, global directory ~/.local/share/m31a-dev, feed development.
• Rollback mechanism restores previous binary from .bak backup if an update fails.