use gpg for ssh

modules/gpg.nix

@@ -3,7 +3,20 @@
     programs.gpg.enable = true;
     services.gpg-agent = {
       enable = true;
+
+      enableSshSupport = true;
+      sshKeys = ["A0B5D579ECACC45C51B2B38E317D346182083CD8"];
+
       maxCacheTtl = 86400; # 1 Day
+      maxCacheTtlSsh = 86400; # 1 Day
     };
+
+    # Disable gnome-keyring-ssh for gpg-agent to work
+    # https://github.com/NixOS/nixpkgs/issues/101616
+    xdg.configFile."autostart/gnome-keyring-ssh.desktop".text = ''
+      [Desktop Entry]
+      Type=Application
+      Hidden=true
+    '';
   };
 }

modules/thunderbird.nix

@@ -4,6 +4,7 @@
 
     profiles.kristian = {
       isDefault = true;
+      withExternalGnupg = true;
     };
   };
 }