Remove overflow: hidden from border-radius utility classes

[sksinha2410]

Border-radius utility classes were causing unintended clipping by unconditionally applying overflow: hidden.

Fix #208

Change

Modified .border-br-{n} class generation in renderers/lit/src/0.8/styles/border.ts:

- .border-br-${idx} { border-radius: ${idx * grid}px; overflow: hidden; }
+ .border-br-${idx} { border-radius: ${idx * grid}px; }

Utility classes should provide single-purpose styling. Components requiring overflow control already apply it explicitly in their component styles (card.ts, image.ts, etc.).

[sksinha2410]

@jacobsimionato