Routing breaks near severances without separately mapped footways

https://www.openstreetmap.org/way/997182611 and nearby -- can't cross at all, so score layer is empty there.

The problem is that we're not walking _along_ Church road, which has sidewalk=both. Methodology really depends on separate footway tagging. We could handle walking along a tagged sidewalk, but we'd need to start tracking side of the road. Alternatively, we could try to automatically generate footways along the main road.

The issue references a specific OSM way (997182611) where routing fails due to missing footway mapping. Start by examining the code that handles sidewalk tagging and routing near severances. Look for modules that process OSM data for sidewalks and generate footways. Determine how side-of-road tracking is currently implemented and test the routing algorithm in that area to see the empty score layer.

Written by the indexing model from the issue text.