Proposal: Get rid of first name / last name, instead use full name

[wkl3nk]

The UI is currently inconsistent:

• The parts that show the user's name based on information from the JWT claim "name": The "name" claim is defined by OpenID Connect as: "End-User’s full name in displayable form including all name parts..."
• The parts that query the Keycloak API for users have first name and last name in separate fields. They are also displayed in the UI in separate columns in tables.

I propose to get rid of first name / last name (both in the backend and the UI) and just use "name" or "fullName" by concatenating first name and last name (from Keycloak).

• This makes it look the same way as in the list of scans, where (if available) the name of the user that triggered the scan is displayed.
• This makes it look the same way as in the own profile page (upper right corner of the UI).
• This allows a more compact presentation in tables.
• Regarding sorting, it makes little sense to sort by first name.