[BUG] Py Module projects can make Back crash : <project_id>/models/ folders not found

This issue may be attributable to volume manipulation or a crash during project creation.

Add a safeguard when a folder is viewed, as it prevents the project from being removed from the dashboard.

Reproduce the crash with a Py Module project whose /models/ folder is missing, then trace project creation, volume handling, and folder viewing. Done means viewing the missing folder no longer crashes the Back or removes the project from the dashboard.

Written by the indexing model from the issue text.