Manual connection: feedback/mopinion - insights. Existing collection fields are not visible when mapping

Major usability issue making onboardings and set up for cusotemrs very difficult and also causing a lot of mistakes.

When connecting a survey to an existing collection, the mapping view does not show or suggest the fields and filters already available in that collection. The person configuring it would need to know the existing structure from memory and enter the mappings manually.

Required: Show the available target fields and values, with suggested mappings where possible.