Refactor endorse popover

[volkyeth]

The current approach of the endorse popover is using the Radix UI popover.
It seems to keep track and update positioning even when the popover is closed. That's causing react render stack overflows (Maximum update depth exceeded) when I use force layouts on #11 and cards are moving a lot and overlapping

We should try https://github.com/floating-ui/floating-ui which seems to support more optimizations

Ideally there would be a single EndorsePopover element which we would render outside the card (like it is with e.g. NegateDialog and MakePointDialog) and then dynamically anchor to the button used to open it