v4.23.0 — Left-side Y-axis and idle rendering

[4.23.0] - 2026-09-22

Added

• LiveChart.isFrameLoopActive accepts a SharedValue<boolean> that suspends
  continuous frame work without disabling pan, zoom, scrub, or draggable
  reference lines.
• LiveChart.debugFrameStats exposes optional development counters for active
  engine frames and tracked engine-state updates.
• yAxis.side: "left" | "right" for single- and multi-series charts. Left labels
  use the caller-reserved insets.left gutter and remain visible above edge fades.

Fixed

• Idle charts settle sub-pixel engine motion, park invisible pulse frames,
  finish candle-width interpolation, and reuse text measurements instead of
  continuously invalidating Skia at the display refresh rate. Resolves
  #304.
• Dragging a reference line no longer opens the scrub crosshair part-way
  through the drag. The scrub pan can activate while a line is being dragged
  and asked its guard with its touch-down point, which a longer drag had
  carried the line away from; a grabbed line now owns the touch outright.