No public user search OR private-flag for user accounts

User Story

As a WIRE User

I want to keep the existence of my WIRE account confidential by default

so that i only get contacted by persons i share my contact details with (e.g. via Live-QR).

Rationale

The current implementation of a public user catalogue where everybody can run search queries by username or profile name is worse than a public telephone book from the 1990th and undermines all principle of privacy.

I doubt that this public search function has any benefit at all.

If the public search persist, a user account should have an additional flag "public / private profile". The default value of this flag should be "private". A private account is not listed anywhere.

This would mitigate security relevant situations as described by other users - like this:
https://support.wire.com/hc/en-us/community/posts/28816739223197-Unwanted-connection-requests-for-my-children