fix: polygon filtered index per layer, instead of per dataset

[igorDykhta]

Summary

Fixes #3277 by applying polygon filters per layer instead of on the shared dataset filteredIndex.

When layers share a dataset (e.g. pickup/dropoff), targeting one layer no longer strips points from the others, and selecting multiple layers no longer ANDs positions across layers.

Changes

• Exclude polygon filters from dataset CPU filtering (getFilterRecord); add filteredIndexByLayer computed per targeted layer
• Layers / Mapbox GL use filteredIndexByLayer[layerId] (fallback: filteredIndex)
• Filtered CSV export and filter plots/histograms apply the union of polygon-visible rows via mergePolygonLayerIndexes
• Clear filteredIndexByLayer on importData / update to avoid stale indexes after Arrow batch reloads
• Use copyTableAndUpdate for the per-layer dataset view (keeps KeplerTable typing)
• Tests for per-layer filtering, disable/restore, export, and plot index merging

Test plan

• nyctrips: polygon-filter pickup only → dropoff unchanged
• Select both layers → each filters on its own positions
• Toggle polygon off → full data restored
• Export filtered data → row count matches polygon-visible rows
• Time/range filter plot updates with an active polygon filter

[Copilot]

Pull request overview

This PR fixes polygon filtering behavior so that polygon filters are applied per-layer rather than at the shared dataset level, preventing unintended cross-layer filtering when multiple layers share a dataset (and avoiding the prior “AND across layers” behavior when multiple layers are selected).

Changes:

• Excludes polygon filters from the dataset-level CPU filter pipeline so dataset.filteredIndex is no longer impacted by polygon filtering.
• Adds filteredIndexByLayer to datasets and computes per-layer polygon-filtered indices in KeplerTable.filterTable.
• Updates layer data/update triggers to use the per-layer filtered index when present, and adjusts unit tests/helpers accordingly.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/node/reducers/vis-state-test.js	Updates polygon filter tests to assert per-layer filtering and unchanged dataset filteredIndex.
test/helpers/comparison-utils.js	Adjusts dataset comparisons to optionally ignore the new internal filteredIndexByLayer field.
src/utils/src/filter-utils.ts	Removes polygon filters from dataset CPU filtering via getFilterRecord while keeping them tracked in the record.
src/table/src/kepler-table.ts	Introduces filteredIndexByLayer and computes per-layer polygon-filtered indices during dataset filtering.
src/layers/src/mapboxgl-layer.ts	Uses per-layer filtered index for update triggers / data building in Mapbox GL layer.
src/layers/src/base-layer.ts	Uses per-layer filtered index when updating meta and calculating data attributes for a layer.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.