Redesigned tabs

[nervenes]

hi! the tabs in zed have always been minimal, slim and nice, but i have had small annoyances with the tabs lately, and i have tried contributing improvements without affecting these characteristics. particularly regarding the padding and the very tiny close button. I've also tried to improve the user experience by merging the dirty buffer indicator with the close button, the full pr for this can be found here: #24453

however, as @maxdeviant pointed out in a comment in the above pr this seems to require a discussion first. so i open this github discussion for us to discuss if and how we can improve the tabs, is my implementation in the pr fine? something that needs to be changed? perhaps, maybe even consider a different approach?

i originally took inspiration from vscode when it comes to merging the dirty buffer indicator with the close button, but as far as i've observed this seems quite common outside vscode as well. this frees up a slot from one side (left or right depending on the close button position in settings) of the tabs while not losing any functionality. all in all, these changes makes very much sense to me, and i would like to think the zed team agrees?

@danilo-leal i tried to get your attention in the above pr, as i remember you mentioned a while back that you wanted to visit the tabs for a redesign, i think we can discuss this here - and i'd be willing to help/contribute!

cc @iamnbutler this might be of your interest too.