0fc8ab1687
Avatars render as circles everywhere (AppHeader, PostCard, profile page), so a square crop frame let users compose an image that looked fine in the cropper and got visibly clipped (lost corners, off-center faces) after upload. Switched the crop frame to a perfect circle by setting borderRadius = CROP_SIZE / 2 on both the frame and the overflow mask. Replaced the four square corner markers with a single thin white ring overlay around the circle. Output is still a 512×512 JPEG — the consumer-side border-radius does the visual circle, so the underlying square is storage-agnostic and re-usable if we ever surface a non-circular avatar elsewhere.