Restructures SSH trust relationships from global to host-specific configuration
for better locality of concern and principle of least privilege.
Changes:
- Collapse nixos/common/global/ssh/ back to ssh.nix (single-file module)
- Move internal host trust (fuchsia/viridian) to per-host services/ssh/
- Split BorgBase known hosts by repository (li9kg944 for fuchsia, r7ag7x1w for viridian)
- Add viridian SSH server config to accept backup connections from fuchsia
- Add fuchsia borgbackup passphrase for offsite backups
- Configure viridian to create /srv/borg-repo/fuchsia for remote backups
This enables the 3-2-1 backup strategy with fuchsia backing up to both viridian
(onsite) and BorgBase (offsite) with proper SSH authentication.
Restructured systemPackages list with alphabetically sorted categories to improve
maintainability and reduce vertical space. Added descriptive comments for all
environment configuration sections.
Add comprehensive inline documentation to both NixOS and Home Manager
global configuration files, explaining the purpose of each section,
overlay usage, unfree package policy, and configuration settings.
Move all allowUnfreePredicate declarations to global configs to prevent
the "last definition wins" merging issue. Unfree packages are now managed
in two central locations:
- NixOS system packages: nixos/common/global/default.nix
- Home Manager packages: home-manager/sajenim/global/default.nix
