hermes-explorigin
86acc56143
Add haversineKm helper and filterStrikesWithinKm filter in src/lib/api/lightning.js. PrecipitationRadar now filters strikes by distance from the current location before projecting them, so only strikes within 25 miles render. No data-source change; relay-down behavior is unchanged. Fixes an incorrect haversine expectation in the test (0.3567 deg of latitude ~= 39.66 km, not 25.7 km).