Fixes
Draw-animation frame no longer touches a destroyed chart
An animated chart (e.g. an area chart) schedules a requestAnimationFrame during render() to run its mask-reveal / draw animation. If the chart was destroyed before that frame fired, the stale callback ran against already-cleared DOM and threw:
TypeError: Cannot read properties of null (reading 'node') // in runMaskReveal
The classic trigger is React StrictMode, which mounts → unmounts → remounts a component in development: the first mount queues the animation frame, the unmount calls destroy() (which nulls w.dom.elDefs), and the queued frame then fires against the torn-down chart. Any sufficiently rapid unmount hit the same race.
The fix adds an internal isDestroyed flag, set by destroy() (but not by updates), that the deferred draw-animation callbacks - mask reveal, stroke draw, and bulk reveal - check and bail on before touching the DOM. The flag is cleared on the next render, so re-mounting re-arms animations normally.
This complements the detached-chart destroy() fix in 5.15.1; together they resolve the teardown crashes tracked in react-apexcharts#602.