pkgs/feeds: make sane.feed-init a buildable package

pkgs/feeds/default.nix

@@ -37,12 +37,7 @@ in rec {  # TODO: make this a scope
       mv update.py $out/bin/update.py
     '';
   };
-  passthru = {
-    updateScript = writeShellScript
-      "feeds-update"
-      (builtins.concatStringsSep "\n" update-scripts);
-
-    initFeedScript = writeShellScript
+  init-feed = writeShellScript
     "init-feed"
     ''
       # this is the `nix run '.#init-feed' <url>` script`
@@ -64,5 +59,10 @@ in rec {  # TODO: make this a scope
       ${update}/bin/update.py "$name" "$json_path"
       cat "$json_path"
     '';
+  passthru = {
+    updateScript = writeShellScript
+      "feeds-update"
+      (builtins.concatStringsSep "\n" update-scripts);
+    initFeedScript = init-feed;
   };
 }