Shared OSM tag-filtering logic used by both the Overpass XML pipeline and
the PBF pipeline. A single source of truth means road-filter rule changes
and POI category additions only need to happen in one place.
Read OpenStreetMap PBF files into the same intermediate shape produced by
the Overpass XML parser. This lets the rest of the pipeline (graph building,
POI extraction) work unchanged whether the data came from live Overpass or
a local PBF file.