Add Linode host configuration and WireGuard setup

- Introduced new configuration files for Linode host, including hardware configuration, toggles, and WireGuard settings.
- Updated flake.nix to include the new images.nix file for Linode image generation.
- Adjusted SSH key paths and secrets management for WireGuard to ensure proper integration with the new host setup.
- Enhanced firewall rules and NAT configuration for WireGuard to improve security and connectivity.

parts/core.nix

@@ -141,7 +141,7 @@ in
         ips: hostName: lib:
         builtins.attrNames ips
         |> builtins.filter (
-          name: !(lib.hasPrefix "wg-" name) && name != "vps" && name != "router" && name != hostName
+          name: !(lib.hasPrefix "wg-" name) && name != "linode" && name != "router" && name != hostName
         );
       shellConditional =
         shellType: bashContent: zshContent:
@@ -204,9 +204,8 @@ in
         miniserver = ../secrets/ssh/ed25519_miniserver.pub;
         galaxy = ../secrets/ssh/ed25519_galaxy.pub;
         phone = ../secrets/ssh/ed25519_phone.pub;
-        vps = ../secrets/ssh/ed25519_vps.pub;
+        linode = ../secrets/ssh/ed25519_linode.pub;
         emacs = ../secrets/ssh/ed25519_emacs.pub;
-        # Build user keys (nixremote)
         nixworkstation = ../secrets/ssh/ed25519_nixworkstation.pub;
         nixserver = ../secrets/ssh/ed25519_nixserver.pub;
         nixminiserver = ../secrets/ssh/ed25519_nixminiserver.pub;