v0.2.0

Added

• Show formatted diffs in an interactive TTY diff viewer with single-column and
  side-by-side layouts, s layout switching, and [/] previous/next change
  block navigation while keeping redirected diff output as unified patch text.
• Show a compact sticky JSON key breadcrumb above the viewer body so deeply
  nested JSON remains anchored to its parent keys while scrolling.
• Add benches/diff-performance.sh for diff model and interactive diff-view
  rendering performance smoke checks.
• Expand the paired diff showcase examples so the interactive diff viewer has
  multiple separated change blocks for layout and jump navigation checks.
• Hide unified-patch control rows in the interactive diff viewer and add
  red/green chunk backgrounds with stronger line-local change highlights.

Changed

• Use softer muted red/green diff backgrounds in the interactive diff viewer.

Fixed

• Clamp interactive diff scrolling to the last full rendered page instead of
  allowing the last row to scroll above an otherwise empty body.
• Base side-by-side diff tail scrolling on the actual rendered diff rows, so
  inserted or deleted blocks use the longer displayed side.