(feat): Smoother corner radius logic for connected/adjacent elements

[SKDemon820]

Describe the behavior you'd like

I'm a big fan of the modern rounded look most OneConfig elements let you use, but there's a minor issue in that every corner gets rounded if you have the option selected, meaning that it's impossible to aggregate multiple HUDs (Ex. multiple different Evergreen elements) into a single unit while retaining a clean rounded corner look — instead there's a chunk taken out at every intersection between HUDs (see screenshot). To make the HUDs look even cleaner, I think there's two ways that corner logic could be improved:

• I feel like this would be a huge pain in the ass to make, but a way to dynamically add an inside radius at the point where any two adjacent HUDs meet that is the same radius as the normal corners (basically the same shape as the negative space left by the normal corner radius, see images for example). If there's ever a case where this wouldn't be possible due to the elements being too similar in size to leave enough room for an inside radius to fit, such as two lines with only slight horizontal differences or a vertical gap that doesn't have enough room to support an interior radius on both sides (Ex. a 10px gap trying to have 2 7px long radii applied to the top and bottom), then the shorter element could be expanded until it snaps to the longer one to create a smooth vertical edge in that spot instead (see image 2).
• If the above system is too complicated, which I imagine it is, then just being able to selectively enable/disable each of the four corners manually would still work fine for many setups. This would at least allow vertical edges to appear smooth without any chunks being removed, meaning people could create a stack of static-size Evergreen elements for example that form a continuous roundtangle for example (How hardcoded multi-line Evergreen HUDs already look, but with whatever lines the user wants).

Additional context