Add contact field "display as" ("show name as")

[miguelmaiquez]

Checklist

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Feature description

Add a "display as" (or "show name as", or "display name") contact field to be able to customise the name of the contact that appears in the list of contacts, calls, sms, email, etc, without having to modify other fields, such as first name and surname.

This new field (not to be confused with the current "nickname" field) should be matching the equivalent field used by other protocols/standards such as carddav, for proper synchronisation with other contact services (Nextcloud, Evolution, Gmail, etc.).

Why do you want this feature?

I have a contact filed as first_name:John surname:Smith, but I would like it to appear as just "John" (or "Dad") in the contact list, calls, email, sms, etc. To do this, I currently have to remove the surname field (Smith), or change the first name field ("John" to "Dad"). I would like to be able to keep the first name and surname fields as they are, while being able to customise the displayed name.

Example:

Prefix: ---
First Name: John
Middle Name: ---
Surname: Smith
Suffix: ---
Display as: Dad
Nickname: ---
...

Additional information

No response

[Aga-C]

It's a duplicate of #129.