Installed initrd lacked mmc_block -> can't mount root on eMMC -> no boot.
generate-config runs in the RAM installer and misses mmc modules, and it
overwrites hardware-configuration.nix, so pin them where they merge instead.
- add disko input; jupiter partitions/formats OS disk declaratively
- hardware-configuration.nix carries kernel modules only (disko owns fileSystems)
- data disk stays a plain unformatted mount, out of disko
- vbox unchanged (virtualbox-image supplies its own disk)
- README: nixos-anywhere remote install + daily rebuild loop
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
erik