Allow ssh access from all user devices

shared/core/ssh.nix

@@ -8,7 +8,12 @@
   };
 
   users.users."riley" = {
+    # Add ssh client
     packages = [ pkgs.openssh ];
+    # Authorize `riley` user on other machines to SSH into this machine.
+    openssh.authorizedKeys.keyFiles =
+      let userKey = sys: ../../system/${sys}/keys/riley.pub;
+      in map userKey [ "dev-lt-63" "strawberry" "lime" ];
   };
 
 }