Mirror the restic system-config adapters for the other two engines, each in that
engine's own convention, so system backup/restore/status/retention work on any
location regardless of engine:
- kopia: BackupSystemToLocation (--tags system:config), SystemSnapshotsJson
(filter tag system:config), RestoreSystemLatest, ForgetSystem (per-source policy
on $configs_dir + maintenance).
- borg: BackupSystemToLocation (archive system-<host>-<ts>, comment system=config;
no app is named "system" so the namespace can't collide), SystemSnapshotsJson
(--glob-archives system-<host>-*), RestoreSystemLatest, ForgetSystem (prune the
system-<host>-* glob).
No dispatcher change needed — engineBackupSystem/SystemSnapshotsJson/
RestoreSystemLatest/ForgetSystem already resolve <engine><fn> per location. All
three engines now define the full set; syntax clean.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>