refactor(network): use address registry

lib/guests.nix

@@ -131,18 +131,6 @@ let
             guest takes its address by DHCP, keeping IP management at the router.
           '';
         };
-        endpoint = {
-          address = lib.mkOption {
-            type = lib.types.nullOr lib.types.str;
-            default = null;
-            example = "10.23.20.126";
-            description = ''
-              Expected IP address assigned outside NixOS for this guest's
-              network endpoint. Left null, this guest contributes no endpoint to
-              the fleet endpoint registry.
-            '';
-          };
-        };
         reverseProxy = reverseProxyRoutes.mkRouteOptions {
           subject = "guest route";
           enableDefault = false;
@@ -290,10 +278,6 @@ let
       config = lib.mkIf cfg.enable {
         sops.secrets = lib.genAttrs cfg.secrets (_: { });
 
-        modules.network.endpoints.${machineName} = lib.mkIf (cfg.endpoint.address != null) {
-          inherit (cfg.endpoint) address;
-        };
-
         modules.reverse-proxy.routes.${machineName} = lib.mkIf cfg.reverseProxy.enable (
           reverseProxyRoutes.routeFields (
             cfg.reverseProxy

lib/network-endpoints.nix

@@ -1,42 +1,19 @@
 { lib }:
 let
-  endpointOptions = {
-    address = lib.mkOption {
-      type = lib.types.str;
-      example = "10.23.20.126";
-      description = "Expected IP address assigned outside NixOS for this network endpoint.";
-    };
-  };
+  endpointFields = address: { inherit address; };
 
-  endpointType = lib.types.submodule {
-    options = endpointOptions;
-  };
-
-  endpointFields = endpoint: {
-    inherit (endpoint) address;
-  };
-
-  collectFleetEndpoints =
-    hosts:
+  collectFleetEndpoints = hosts:
     lib.concatMapAttrs (
       hostName: host:
-      let
-        cfg = host.config.modules.network;
-        hostEndpoint = lib.optionalAttrs (cfg.endpoint.address != null) {
-          ${hostName} = endpointFields cfg.endpoint;
-        };
-        guestEndpoints = lib.mapAttrs' (
-          endpointName: endpoint: lib.nameValuePair "${hostName}-${endpointName}" (endpointFields endpoint)
-        ) cfg.endpoints;
-      in
-      hostEndpoint // guestEndpoints
+      lib.mapAttrs' (
+        entryName: address:
+        let
+          endpointName = if entryName == "self" then hostName else "${hostName}-${entryName}";
+        in
+        lib.nameValuePair endpointName (endpointFields address)
+      ) (host.config.registry.address.${hostName} or { })
     ) hosts;
 in
 {
-  inherit
-    collectFleetEndpoints
-    endpointFields
-    endpointOptions
-    endpointType
-    ;
+  inherit collectFleetEndpoints endpointFields;
 }