perf(tracks): coalesce address lookups

vehicle-data-platform/apps/web/src/v2/domain/track.ts

@@ -1,5 +1,22 @@
 import type { HistoryLocationRow, TrackPlaybackEvent, TrackPlaybackResponse } from '../../api/types';
 
+export const TRACK_ADDRESS_SETTLE_MS = 650;
+
+export type TrackAddressCoordinate = { longitude: number; latitude: number; key: string };
+
+export function trackAddressCoordinate(longitude?: number, latitude?: number): TrackAddressCoordinate | undefined {
+  if (!Number.isFinite(longitude) || !Number.isFinite(latitude)
+    || Math.abs(longitude ?? 0) > 180 || Math.abs(latitude ?? 0) > 90
+    || (longitude === 0 && latitude === 0)) return undefined;
+  const roundedLongitude = Number(longitude!.toFixed(4));
+  const roundedLatitude = Number(latitude!.toFixed(4));
+  return {
+    longitude: roundedLongitude,
+    latitude: roundedLatitude,
+    key: `${roundedLongitude.toFixed(4)},${roundedLatitude.toFixed(4)}`
+  };
+}
+
 export function formatDuration(seconds: number) {
   const safe = Math.max(0, Math.floor(seconds || 0));
   const hours = Math.floor(safe / 3600);