Conscript install is incredibly opinionated to use bash shell

It's impossible to run the conscript install script on any shell other than bash and expect it to work without making manual changes to the install script.

Inspect the conscript install script and reproduce the installation from a non-bash shell, noting which bash-specific behavior prevents it from running. Done means the script can be run without manual edits from the affected shell; the issue does not name a specific file, shell, or test.

Written by the indexing model from the issue text.