before_after_slider

• Added SliderOrientation support (horizontal / vertical).
• Improved gesture/render performance in slider and zoom paths.
• Improved pinch responsiveness during active scale gesture.
• Optimized showcase rebuild behavior and simplified showcase controls.

Breaking

• BeforeAfter now uses grouped options:
  • interactionOptions
  • zoomOptions
  • labelsOptions
  • overlayOptions
• Removed legacy top-level params (enableProgressWithTouch, enableZoom, overlayStyle, legacy labels/overlay params, fixedLabels).

Added

• Desktop/web pointer cursor customization.
• autoViewportAspectRatioFromImage when viewportAspectRatio is not provided.
• Integration tests and drag/zoom benchmark scenarios (example/integration_test).

Fixed

• Slider drag conflict while panning zoomed content.
• Pan bounds clamping to avoid visible blank background.
• Desktop/web pointer zoom consistency.

Performance

• Reduced gesture/render rebuild pressure on hot paths.
• Optimized image stream reuse for auto viewport ratio flow.

Migration

• Upgrade notes: see README.md (Migration section).

• BREAKING: removed BeforeAfterImage and BeforeAfterLayout.
• BREAKING: BeforeAfter is now the single public widget API:
  • BeforeAfter(beforeChild: ..., afterChild: ...)
• BREAKING: removed direct beforeLabel and afterLabel params.
  • Use beforeLabelBuilder and afterLabelBuilder.
• Inlined comparison implementation into BeforeAfter and removed extra wrapper/core layers.
• Updated docs and examples for the new API.

• Added beforeLabelBuilder and afterLabelBuilder for custom label widgets.
• Added a new labels demo tab in the example app.
• Improved rendering performance with repaint isolation and progress notifier updates.
• Optimized clipping and zoom/pan update flow for smoother interactions.

• Fix version alignment between CHANGELOG and pubspec.