0055951: [24Q3] Name showing instead of username in the Login screen

When no picture is available in the User window, it should show the first character from the first name 
and the one from the last name, both in uppercase.
Example:
Jane Green Smith will display “JG”
jane green smith will display “JG”
JANE GREEN SMITH will display “JG”
If there is only one first name, then the two first characters of this word, the first in uppercase and 
the second in lowercase.:
Example:
Jane will display “Ja”.
jane will display “Ja”.
JANE will display “Ja”.
If there is no first name or last name, it should show the two first characters of the user name, the 
first in uppercase and the second in lowercase.

Example:
Jane will display “Ja”.
jane will display “Ja”.
JANE will display “Ja”.
It should have a random background color based on the UUID, but the same UUID icon will always have the 
same background color (i.e. if 432A3439F3GB…is randomly red, it will always be red). The top-right 
user circle present in portrait mode to access the user popover should be changed also to randomize based 
on UUID.

The color of the text should be black or white following the same logic/algorithm that we have in product 
keymap buttons

In the POS login screen,
* If ‘Alias’ is informed, the ‘Alias’ should be displayed instead of the username.
* If ‘Alias’ is not informed, the username should be displayed.