nodejs/importNpmLock: init source overrides option

    # Example: { "node_modules/axios" = { curlOptsList = [ "--verbose" ]; }; }

    # This will download the axios package with curl's verbose option.

    , fetcherOpts ?  {}

    # A map from node_module path to an alternative package to use instead of fetching the source in package-lock.json.

    # Example: { "node_modules/axios" = stdenv.mkDerivation { ... }; }

    # This is usefull if you want to inject custom sources for a specific package.

    , packageSourceOverrides ? {}

    }:

    let

      mapLockDependencies =

          mapAttrs

            (modulePath: module:

              let

                src = fetchModule {

                src = packageSourceOverrides.${modulePath} or (fetchModule {

                  inherit module npmRoot;

                  fetcherOpts = fetcherOpts.${modulePath} or {};

                };

                });

              in

              cleanModule module

              // lib.optionalAttrs (src != null) {