Improve IP selection near threat zone centers.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2754.

client/src/api/_liberationApi.ts

@@ -384,6 +384,8 @@ export type IpZones = {
   ipBubble: LatLng[][];
   permissibleZone: LatLng[][];
   safeZones: LatLng[][][];
+  preferredThreatenedZones: LatLng[][][];
+  tolerableThreatenedLines: LatLng[][];
 };
 export type JoinZones = {
   homeBubble: LatLng[][];