chore(modules/firewall): Rewrite to simplify

Also disable the ai filter for nodes that don't have nginx enabled

modules/nixos/dgn-firewall/default.nix

@@ -3,9 +3,9 @@
 # SPDX-License-Identifier: EUPL-1.2
 
 {
-  pkgs,
+  config,
   lib,
-  name,
+  pkgs,
   ...
 }:
 
@@ -13,6 +13,7 @@ let
   inherit (lib)
     concatStringsSep
     length
+    optionalAttrs
     replicate
     splitString
     ;
@@ -85,7 +86,9 @@ in
 
       stop = [ (nft "delete table inet reaction") ];
 
-      streams = streams'.default // (streams'.${name} or { });
+      streams = {
+        inherit (streams') ssh;
+      } // (optionalAttrs config.services.nginx.enable { inherit (streams') ai-crawlers; });
     };
   };
 }

modules/nixos/dgn-firewall/streams.nix

@@ -23,8 +23,9 @@ let
       cmd = act "delete";
     };
   };
+in
 
-  available = {
+{
   ai-crawlers = {
     cmd = [
       "tail"
@@ -79,12 +80,4 @@ let
       };
     };
   };
-  };
-in
-
-builtins.mapAttrs (_: builtins.foldl' (a: s: a // { ${s} = available.${s}; }) { }) {
-  default = [
-    "ai-crawlers"
-    "ssh"
-  ];
 }