feat(ui): add collapsible layer groups and base-layer previews

[pjeweb]

Summary

• Add opt-in collapsibleGroups on the layer switcher with visible/total counts.
• Allow optional base-layer preview thumbnails on split base-layer entries.

[changeset-bot]

🦋 Changeset detected

Latest commit: 22442d1

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 4 packages

Name	Type
@mapsight/ui	Minor
@mapsight/core	Patch
@mapsight/count-aggregator-ui	Major
@mapsight/showcase	Patch

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[Copilot]

Pull request overview

This PR adds opt-in UI capabilities to the layer switcher: collapsible overlay groups (with visible/total counts) and optional preview thumbnails on split base-layer entries, backed by new config and metadata fields.

Changes:

• Add collapsibleGroups option to the UI layer switcher and implement collapsible overlay groups (split base-layers mode) with visible/total counts.
• Add optional layerSwitcherPreviewUrl layer metadata and plumb it through to switcher entries for base-layer preview thumbnails.
• Add new SCSS for the collapsible group toggle/chevron and preview thumbnail elements.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
packages/ui/src/scss/blocks/_layer-switcher.scss	Adds styles for entry previews and collapsible group toggles/chevrons.
packages/ui/src/js/types.ts	Extends layer switcher config state with collapsibleGroups.
packages/ui/src/js/index.ts	Sets default collapsibleGroups: false in create options and expands selection behavior comments.
packages/ui/src/js/components/switcher/SwitcherEntry.tsx	Adds previewUrl rendering and --with-preview modifier support.
packages/ui/src/js/components/layer-switcher/SplitBaseLayerSwitcher.tsx	Implements collapsible overlay groups (split mode) and visible/total counts.
packages/ui/src/js/components/layer-switcher/LayerSwitcherEntry.ts	Plumbs layerSwitcherPreviewUrl metadata into SwitcherEntry as previewUrl.
packages/ui/src/js/components/layer-switcher/LayerSwitcherContainer.tsx	Exposes collapsibleGroups prop and passes it to the split switcher.
packages/ui/src/js/components/layer-switcher/index.ts	Wires collapsibleGroups from config into the container props.
packages/core/src/js/lib/map/schema.ts	Adds layerSwitcherPreviewUrl to the layer metadata schema.
.changeset/ui-layer-switcher-collapsible-previews.md	Declares version bumps for @mapsight/ui (minor) and @mapsight/core (patch).

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[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated no new comments.

Suppressed comments (1)

packages/ui/src/js/components/layer-switcher/SplitBaseLayerSwitcher.tsx:88

• translate("ui.layer-switcher.expandGroup") / translate("ui.layer-switcher.collapseGroup") are referenced here, but those keys are not present in the current i18n catalogs (e.g. packages/ui/src/js/helpers/i18n/en.ts and de.ts). This will likely render the raw key string in the UI. Add these translations (and any other supported locales) or change the code to use existing keys.

	const countLabel = `${visibleCount}/${total}`;
	const toggleLabel = collapsed
		? translate("ui.layer-switcher.expandGroup")
		: translate("ui.layer-switcher.collapseGroup");