ID15.2 Add private notes (Backend)

[paarals]

Is your feature request related to a problem? Please describe.

Describe the solution you'd like
If in the future, both public and non-public suggestions are needed, as a vluator (and process-admin) i want two separate fields for an answer - one for a public answer (as seen with proposals) and one with a priate answer (see #15.1)

Mock up

Does this issue could impact on users private data?

Acceptance criteria

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Technical specifications

Implementation

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Testing

Additional context