- Rename variants/ to hw/ for clearer hardware module naming
- Rename glue/ to fleet/ for more intuitive fleet management
- Move boot/fs configuration from glue/boot.nix to separate fleet/boot.nix and fleet/fs.nix
- Improve separation of concerns between boot, filesystem, and common config
- Add glue/ for fleet generation logic and common configuration
- Add variants/ for hardware type modules
- Improves separation of concerns and module organization