Keep a route out of a drawn area

POST /route and POST /isochrone accept avoid_areas: a GeoJSON ring whose roads are removed from the search.

• A polygon, MultiPolygon, or FeatureCollection of either, on route, isochrone, matrix, match and optimized-route
• At most 8 rings, 100 vertices and 10 km of perimeter; a ninth ring is 400 from the gateway
• A destination inside the ring is 422, not a route that crosses it

AvailabilityA destination inside the ring is rejected. Valhalla 3.8.3 can still snap a point across the polygon, so treat the ring as a strong exclusion, not a guarantee.