bazel: `copy_directory`, `copy_to_directory` bits are not in the `distdir`

These directories are mirrored and the repositories are initialized in `build/nodejs.bzl`, but the stuff is not captured from `generate-distdir`.

Separately, we should evaluate if future versions of `rules_js` will still need this utility. If not, then this stuff can be removed from our repo.

This item may become stale if [DEVINF-1126](https://cockroachlabs.atlassian.net/browse/DEVINF-1126) is worked on.

Epic: CRDB-17171

Jira issue: CRDB-38258

Start with build/nodejs.bzl and the generate-distdir process to trace how the mirrored repositories are initialized and which contents are captured. Confirm whether copy_directory and copy_to_directory need to appear in distdir, or whether the related utility should be removed based on future rules_js needs; the issue is done when the chosen path is reflected in the repository and distdir behavior.

Written by the indexing model from the issue text.