Feat(templates): export clan templates statically

lib/build-clan/interface.nix

@@ -213,6 +213,8 @@ in
 
           secrets = lib.mkOption { type = lib.types.raw; };
 
+          templates = lib.mkOption { type = lib.types.raw; };
+
           machines = lib.mkOption { type = lib.types.raw; };
         };
       };

lib/build-clan/module.nix

@@ -250,6 +250,9 @@ in
       # We should have only clan.modules. (consistent with clan.templates)
       inherit (clan-core) clanModules;
 
+      # Statically export the predefined clan modules
+      templates = clan-core.clan.templates;
+
       secrets = config.secrets;
 
       # machine specifics