Point to the persistent paths for SSH keys to make sops work.

common/global/sops.nix

@@ -1,5 +1,10 @@
 {
   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"
+    ];
   };
 }