Summary

Follow-up to #22518 (the progressive scatter renderer), requested in this review comment and tracked in #22731.

When the progressive renderer is active on a large scatter dataset, zooming or panning used to repaint every visible point on each interaction frame. The progressive batching only protected the first paint, not the interaction, so large datasets could stutter while the user zoomed or panned.

This PR makes the progressive scheduler zoom aware: while a zoom or pan interaction is in progress, only the first batch of each series is painted, which keeps every interaction frame cheap. Once the interaction settles, the remaining batches are revealed progressively, exactly like the initial paint.

How it works

• The scheduler now reads selectorChartZoomIsInteracting. While it is true, revealedRounds is capped to the first batch (INTERACTION_REVEALED_ROUNDS = 1).
• When it becomes false again, the existing animation frame ramp resumes from the current reveal count up to the full count.
• The "delay of inactivity" reuses the zoom plugin's existing 166ms isInteracting debounce, which is the same signal the line, bar, and area charts already use to skip animation during zoom. No new timer is introduced.
• useProgressiveRendering now declares UseChartCartesianAxisSignature as a dependency (it is always registered before progressive rendering in every chart), mirroring useChartClosestPoint.

Behavior

• Pro charts with the progressive renderer: during zoom or pan only the first batch repaints; the rest fill in once the interaction stops.
• Community charts: no change. Zoom is a Pro feature, so isInteracting stays false and the renderer behaves exactly as before.
• No public API change.

Testing

Added ScatterChartPro.progressive.test.tsx: it renders 1500 points with renderer="svg-progressive", asserts all 1500 markers are revealed at rest, that the count drops to the first batch (1000) during a zoom interaction, and that it returns to 1500 after the interaction settles.

Verified locally: TypeScript (x-charts, x-charts-pro, x-charts-premium), ESLint, and the existing scatter test suites all pass.

Closes #22731

Changelog

[charts] The progressive scatter renderer now stays fluid while zooming and panning: it paints only the first batch during the interaction and reveals the rest once it settles.

• I have followed (at least) the PR section of the contributing guide.