Optimize mover rendering and segment plan pipeline

tests/UnitLayerTrailLifecycle.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+import { pruneInactiveTrails } from "../src/client/graphics/layers/TrailLifecycle";
+
+describe("UnitLayer trail lifecycle helpers", () => {
+  it("removes transport and nuke trails for inactive units", () => {
+    const nukeTrails = new Map<number, number[]>([
+      [10, [1, 2, 3]],
+      [11, [4, 5]],
+    ]);
+    const transportTrails = new Map<number, { xy: number[] }>([
+      [10, { xy: [1, 1, 2, 2] }],
+      [12, { xy: [5, 5, 6, 6] }],
+    ]);
+
+    const result = pruneInactiveTrails(
+      nukeTrails,
+      transportTrails,
+      (unitId) => unitId === 11,
+    );
+
+    expect(result).toEqual({ removedNukes: 1, removedTransport: 2 });
+    expect(Array.from(nukeTrails.keys())).toEqual([11]);
+    expect(transportTrails.size).toBe(0);
+  });
+
+  it("keeps all trails when units are active", () => {
+    const nukeTrails = new Map<number, number[]>([[1, [1]]]);
+    const transportTrails = new Map<number, { xy: number[] }>([
+      [2, { xy: [0, 0, 1, 1] }],
+    ]);
+
+    const result = pruneInactiveTrails(
+      nukeTrails,
+      transportTrails,
+      () => true,
+    );
+
+    expect(result).toEqual({ removedNukes: 0, removedTransport: 0 });
+    expect(nukeTrails.size).toBe(1);
+    expect(transportTrails.size).toBe(1);
+  });
+});