/infra/web/terragrunt.hcl

terragrunt no longer hangs when download_dir is a non-hidden subdirectory of the unit

Setting download_dir (via the attribute, --download-dir, or TG_DOWNLOAD_DIR) to a subdirectory of the unit's working directory whose name did not start with a dot caused commands that prepare the OpenTofu or Terraform source (apply, plan, run, and similar) to hang.

For example:

# /infra/web/terragrunt.hcl
download_dir = "cache"

terraform {
  source = "./mod"
}

Here terragrunt apply would copy ./mod into cache/, see the new cache/ directory on the next read of the unit, and recurse into it. The default .terragrunt-cache was unaffected because Terragrunt's source-copy step skips any directory whose name starts with a dot.

These configurations now produce an immediate error identifying the source and destination paths.