[auth] Increase code density

[dnred]

Currently there is a lot of wasted space that could be used to display even more codes in compact mode.

This is an example from Stratum Auth (Authenticator Pro):

Also just found out another way older feature request for this: #1030

[kaizokan]

For some it's wasted space for others it's "Less is more" ; ) and for others it could be privacy (showing less of which accounts you own).
I personally like the one item per row in compact mode but that is just me.

I don't know about you and others, but I personally do not use the "Next code" and even have my codes hidden anyway. If such a grid mode is used maybe the "Next code" can be removed to have more space? I don't know how often "Next code" is used, I guess that also depends on whether users copy the code or switch back and forth to enter the code (which can take longer). I personally never use it and codes that have disappeared (but copied or remembered) can still be used based on my experience. Just sharing my thoughts.