clan-template: introduce clan-flake-module

templates/new-clan/clan-flake-module.nix

@@ -0,0 +1,9 @@
+# AUTOMATICALLY GENERATED by clan
+{ ... }: {
+  imports =
+    let
+      relPaths = builtins.fromJSON (builtins.readFile ./imports.json);
+      paths = map (path: ./. + path) relPaths;
+    in
+    paths;
+}