support multiple hierarchies in `facets` builder

[bilalesi]

Environment

E.g. dev, staging, prod

Operating system & resolution

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Browser & version

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Description

currently, the facets builder logic in WithFacets class and _get_facets function doesn't account for multiple brain region hierarchies when filtering data, the InBrainRegionQuery dependency supports filtering by a specific within_brain_region_hierarchy_id, but when facets are built, they aggregate results across all hierarchies without respecting the hierarchy context specified in the query parameters.

To Reproduce

Expected behavior

• apply hierarchy filtering in facet queries when hierarchy_id is provided

Screenshots

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Additional context

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Acceptance criteria

• Facets respect within_brain_region_hierarchy_id when provided
• Facet counts only include entities from the specified hierarchy

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Will be added by default (the Product Owner)

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Type

Bug

Projects

Select 'OBI 2025-' project (plus others as relevant)
Priority: P1
Time estimate: In days

[bilalesi]

@GianlucaFicarelli I will add the same priority as the related ticket is that okey ?