the star and fork controls hand-rolled their own joined-group wrapper and then forced their buttons to min-h-7.5 to fit inside a max-h-8 box, so they came out shorter than every other button on the platform. both now use ButtonGroup, which does the radius collapsing and border overlap already, and the buttons keep their own size, and the signed-out stars link becomes a Button instead of an anchor styled to look like one. measured on the repo header story: the stars control and the fork pair are both 34px now, where the pair used to be 36px and its segments 30px. Signed-off-by: eti <eti@eti.tf>