fix(interaction): brushXFilter/brushYFilter should not modify the non-filtered axis scale

[Copilot]

brushXFilter was hiding and overwriting the Y axis scale domain (and vice versa for brushYFilter), causing Y axis ticks to change after an X-only brush filter operation.

Root causes

• BrushFilter defaulted hideY: true for all subclasses, including BrushXFilter — causing the Y axis to flash hide/show during re-render, appearing as a tick change
• BrushFilter unconditionally set both scale.x.domain and scale.y.domain with nice: false, even when only one axis was being filtered — potentially producing different tick positions than the original scale

Changes

• brushFilter.ts: Add filterX and filterY boolean params to BrushFilter. Before applying the filter state, the current domain of each non-filtered axis is captured directly from newView.scale and explicitly preserved with nice: false, so it is never subject to re-inference:

  const preservedDomainY = !filterY && currentScale.y
    ? currentScale.y.getOptions().domain : null;
  // ...
  scale: {
    ...(filterX && { x: { domain: domainX, nice: false } }),
    ...(filterY && { y: { domain: domainY, nice: false } }),
    ...(preservedDomainX && { x: { domain: preservedDomainX, nice: false } }),
    ...(preservedDomainY && { y: { domain: preservedDomainY, nice: false } }),
  }

• brushXFilter.ts: Pass hideY: false, filterY: false — Y axis is not hidden and its domain is explicitly preserved when filtering X
• brushYFilter.ts: Pass hideX: false, filterX: false — X axis is not hidden and its domain is explicitly preserved when filtering Y
• interaction.spec.ts: Add unit tests asserting Y domain is unchanged after brushXFilter and X domain is unchanged after brushYFilter

Explicitly preserving the current domain (rather than relying on re-inference) ensures correctness even when nice: true is configured or when another filter (e.g. a slider) has already modified the non-filtered axis domain.

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[moayuisuda]

@copilot not work, it's y axis domain still changed after brush

[Copilot]

@copilot not work, it's y axis domain still changed after brush

The previous fix relied on scale re-inference for non-filtered axes, which could produce a different domain in some edge cases (e.g. when nice: true is set, or when other filters like a slider have modified the current scale domain).

The updated fix (commit 31e4115) now explicitly captures and preserves the current domain of the non-filtered axis directly from newView.scale before the filter is applied:

const preservedDomainY = !filterY && currentScale.y
  ? currentScale.y.getOptions().domain : null;
// ...
...(preservedDomainY && { y: { domain: preservedDomainY, nice: false } }),

This guarantees the Y domain stays exactly the same after brushXFilter (and likewise for X after brushYFilter), regardless of how the scale was originally configured.