- Replaced perimeter-based border animation with a bottom-edge `borderSegmentHeadCol` bounce cycle.
- Constrained animated segment rendering so only the bottom border can be darkened while other edges stay flat accent.
- Updated tests to validate non-teleporting width-based motion and bottom-edge easing behavior.
- Added clockwise sweeping dark segment animation to output block borders while bash/eval tool calls are pending/running.
- Changed bash renderCall to immediately render a full bordered block instead of a one-liner status preview, so silent commands show the framed block for their entire runtime.
- Added shimmerEnabled() helper and wired animate flag through OutputBlockOptions, CodeCellOptions, and shell/eval renderers.