Prod logs showed road_proximity took 186 s on a single Calculate.
Req's receive_timeout only catches TCP idle, not slow streaming, so a
trickling Overpass response could not be cancelled. Wrap the call in a
Task.yield/shutdown deadline and cache successful results by 0.05°-rounded
bbox so adjacent Calculates skip Overpass entirely.
Calculate occasionally hung in production for ~30s. Adds per-phase
timing logs to Compute.run so the slow step is visible in pod logs,
and trims the Overpass road-proximity request to a 10s server-side
timeout / 12s receive timeout (no Req retries) so a slow road API
fails soft to no road penalty instead of stalling Calculate.
- Local prominence: each cell's elevation vs. its 8-neighbor ring
(~1.3 km radius) feeds a small additive bonus so broad hilltops
rank above isolated SRTM voxels
- Road proximity: one Overpass call per Calculate fetches drivable
ways inside the bbox; cells beyond ~0.5 km of any road get a
light dB penalty, gated off in tests
