Railways should be visible at lower zooms

[russss]

As far as I can tell, railways are currently not included in the tiles until zoom level 11. I'd argue that mainline railways are equally important as major roads, and so should be visible at the same zoom level.

[bdon]

This is consistent with the existing tilezen implementation at https://pmtiles.io/?url=https%3A%2F%2Fr2-public.protomaps.com%2Fprotomaps-sample-datasets%2Ftilezen.pmtiles#map=7.44/51.399/-0.829 - kind=rail as part of road should appear at MapLibre z10, this is the physical infrastructure. There will eventually be a transit layer (https://docs.protomaps.com/basemaps/layers#transit) for passenger services that is generalized to MapLibre z14 as seen in the above link.