Idea: Leave item type external survey open

This is a request by Marta Mezzanzanica from the National Centre for Social Research (UK)

Use Case: As a researcher, I would like to keep the link to an external survey open in the inbox (in order to manage participation in the external survey tool). When a participant confirms to be redirected to the external survey tool, the appkit survey should not be counted as "submitted" and not be labelled as "closed" in the inbox, but stay available for later re-opeing.

Requirements:

1. This feature should not replace the external survey item type as it is, but be realised as an alternative option to the existing setting (of closing a survey in the appkit inbox after confirming the redirection to the external survey tool).
2. It might already be covered by this feature: appkit#6