refactor(deploy): move deployment config into '<host>/meta.nix'

hosts/eetion/default.nix

@@ -13,7 +13,6 @@
   ];
 
   ssh = {
-    publicHostname = config.host.name;
     authorizedHosts = [
       "andromache"
       "astyanax"

hosts/eetion/meta.nix

@@ -1,5 +1,9 @@
 {
   system = "aarch64-linux";
-  deployment.tags = [ "arm" ];
+  deployment = {
+    tags = [ "arm" ];
+    targetHost = "eetion";
+    targetUser = "h";
+  };
   role = "embedded";
 }