fix boat trail on alternate view

src/client/graphics/layers/UnitLayer.ts

@@ -203,6 +203,18 @@ export class UnitLayer implements Layer {
       ?.[GameUpdateType.Unit]?.forEach((unit) => {
         this.onUnitEvent(this.game.unit(unit.id));
       });
+    this.boatToTrail.forEach((trail, unit) => {
+      for (const t of trail) {
+        this.paintCell(
+          this.game.x(t),
+          this.game.y(t),
+          this.relationship(unit),
+          this.theme.territoryColor(unit.owner()),
+          150,
+          this.transportShipTrailContext,
+        );
+      }
+    });
   }
 
   private relationship(unit: UnitView): Relationship {
@@ -365,8 +377,6 @@ export class UnitLayer implements Layer {
   }
 
   private handleTradeShipEvent(unit: UnitView) {
-    const rel = this.relationship(unit);
-
     // Clear previous area
     for (const t of this.game.bfs(
       unit.lastTile(),