Nicos: auto-save scripts before submitting

As a user I would like nicos to autosave my script somewhere before submitting it to the script server, so that I can refer back to it later if needed.

Requested by scientist at training session

The issue names Nicos and the script server but does not identify files or tests. Start by locating Nicos' script-submission entry point and the script-server integration; the work is done when a script is saved somewhere before submission and can be referred to later.

索引モデルが issue の本文から書いたものです。