Merge two notes/events into a single record

[sleidig]

It may happen that two users record notes on the same issue. Or more commonly: there may be events (e.g. a workshop) where two groups have actually been participating together.
In this case users may afterwards want to combine the two entries into a single note/event that includes all participants and details of both merged records.

Proposed Solutions & Alternatives
The tasks and workflow could be like this (further discussion welcome):

• add a way to select multiple rows in a table (i.e. multiple notes in the Notes List)
• add a UI to perform actions on all the selected rows (this could also include "delete all", etc.)
• add an action "merge selected", which will open the Note Details form filled with a combination of data of the records to be merged
• if the user clicks "cancel", no merge happens; if the user clicks "save", the selected merged records are removed and the combined new one is saved

Merging two records should mean:

• participants, groups and authors of the records are combined
• details are kept if they are matching (e.g. interaction category, same title, ...)
• details that are not matching are appended (e.g. note text or titles) or using the data of one of the records (e.g. interaction category); the form should visually highlight these fields so that the user can review and correct that

[sleidig]

Thanks for working out details of this feature and creating the sub-issues, @george-neha !
Could you please also paste screenshots of your early draft mocks. This will be very useful to discuss and inform the next level of detail for the implementation, in the respective sub-issue 🙂

Let's refine the first sub-issue #2855 first, until different developers do not have any open questions remaining when reading this.

[sleidig]

ideally, the headers (title "Merge Preview" column etc.) in the merge dialog would stay visible fixed, rather than scrolling out?