ssh: add keys to agent (new config syntax), remove heimdall

Set TERM env var to xterm-256color in foot config instead of as ssh
override, might fix emacs remote shell issues where it should be
TERM=dumb

programs/desktop/foot/default.nix

@@ -8,6 +8,7 @@
     server.enable = true;
     settings = {
       main = {
+        term = "xterm-256color";
         locked-title = false;
         font = "${fonts.monospace.name}:size=${toString fonts.sizes.applications}";
         dpi-aware = false;

programs/shell/ssh.nix

@@ -5,16 +5,13 @@
   ];
   programs.ssh = {
     enable = true;
+    addKeysToAgent = "yes";
     forwardAgent = true;
     compression = true;
     serverAliveInterval = 15;
     serverAliveCountMax = 3;
     controlMaster = "auto";
     controlPersist = "10s";
-    extraConfig = ''
-      AddKeysToAgent=yes
-      SetEnv TERM=xterm-256color
-    '';
     matchBlocks = {
       "git*".user = "git";
       "legion" = {
@@ -32,12 +29,6 @@
       "freia" = {
         user = "elitherl";
         hostname = "freia027.hpc.l";
-        forwardX11Trusted = true;
-      };
-      "heimdall" = {
-        user = "elitherl";
-        hostname = "heimdall003.jet.uk";
-        forwardX11Trusted = true;
       };
     };
   };