feat(hm): add sharedModules, move configurations.nix to hosts.nix

nix/modules/home-manager.nix

@@ -1,13 +1,18 @@
-{ inputs, ... }:
+{ inputs, config, ... }:
 let
+  inherit (cfg.lib) flattenAttrs;
+  cfg = config.flake;
   hm = inputs.home-manager;
   globalCfg = {
-    home-manager.useGlobalPkgs = true;
-    home-manager.useUserPackages = true;
+    useGlobalPkgs = true;
+    useUserPackages = true;
+    sharedModules = [
+      (flattenAttrs (cfg.modules.homeManager or { }))
+    ];
   };
 in
 {
   imports = [ hm.flakeModules.home-manager ];
   flake.modules.nixos.default.imports = [ hm.nixosModules.home-manager ];
-  flake.modules.nixos.default.config = globalCfg;
+  flake.modules.nixos.default.config.home-manager = globalCfg;
 }

nix/modules/hosts.nix

@@ -0,0 +1,34 @@
+{
+  config,
+  lib,
+  inputs,
+  ...
+}:
+let
+  inherit (lib) nixosSystem;
+  inherit (cfg.lib) flattenAttrs;
+  inherit (lib.attrsets) mapAttrs;
+  cfg = config.flake;
+  hosts = cfg.manifest.hosts or { };
+  mkConfigurations =
+    class: hosts:
+    mapAttrs (
+      name: value:
+      if class == "nixos" then
+        nixosSystem {
+          specialArgs = {
+            inherit inputs;
+            hostName = name;
+          };
+          modules = [
+            (flattenAttrs cfg.modules.nixos)
+            (value.extraCfg or { })
+          ];
+        }
+      else
+        { }
+    ) hosts;
+in
+{
+  flake.nixosConfigurations = mkConfigurations "nixos" hosts.nixos;
+}