PooledGeometryType, NOT GeometryTypeName: only POOLED geometry types have
buffers here (see pooled in types/geometry-capabilities). A type rendered from
a plain BufferGeometry — mesh — never reaches the pool, so do not widen this
to the geometry vocabulary when a geometry type is added. Keyed off the shared
union rather than spelled out, so adding a POOLED type is a compile error while
adding a non-pooled one correctly requires no change here.
A pooled THREE geometry, plus the metadata the pool needs to decide reuse, eviction, and frame accounting.
(The former
attributeTypes?: PointsAttributeTypesdtype snapshot is gone: points moved to the fixed 3-texel texture layout, so any pooled points geometry fits any points node — dtype normalization happens at upload time, not in the buffer layout.)