WIP: per-machine kopia secrets.

Cleanup unused kopia VM config.

common/global/sops.nix

@@ -1,10 +1,16 @@
+{ config, ... }:
 {
   sops = {
-    defaultSopsFile = ./../../secrets/secrets.yaml;
     # sometimes the impermanence bind mount is stopped when sops needs these
     age.sshKeyPaths = [
       "/persist/etc/ssh/ssh_host_ed25519_key"
       "/persist/etc/ssh/ssh_host_rsa_key"
     ];
+    defaultSopsFile = ./../../secrets/common.yaml;
+    secrets = {
+      kopia = {
+        sopsFile = ./../../secrets/${config.networking.hostName}.yaml;
+      };
+    };
   };
 }