feat(timeline): integrate timeline functionality into game client

- Added TimelineController to manage timeline events and state.
- Introduced TimelinePanel for user interaction with the timeline.
- Implemented LruCache for efficient storage of timeline records.
- Enhanced Transport and GameRenderer to support timeline features.
- Updated various layers to respond to timeline events, ensuring synchronization with game state.
- Added support for seeking and jumping within the timeline, improving user experience during gameplay.

This commit lays the groundwork for a more interactive and responsive timeline feature in the game client.

tests/GameMapMutableState.test.ts

@@ -0,0 +1,45 @@
+import { describe, expect, it } from "vitest";
+import { GameMapImpl } from "../src/core/game/GameMap";
+
+describe("GameMapImpl mutable state", () => {
+  it("exports and imports mutable state losslessly", () => {
+    const w = 4;
+    const h = 3;
+    const terrain = new Uint8Array(w * h).fill(1 << 7); // mark as land
+
+    const map1 = new GameMapImpl(w, h, terrain, w * h);
+    const t0 = map1.ref(0, 0);
+    const t1 = map1.ref(1, 0);
+    const t2 = map1.ref(2, 0);
+
+    map1.setOwnerID(t0, 123);
+    map1.setFallout(t1, true);
+    map1.setDefenseBonus(t2, true);
+
+    const exported = map1.exportMutableState();
+
+    const map2 = new GameMapImpl(w, h, terrain, w * h);
+    map2.importMutableState(exported.state, exported.numTilesWithFallout);
+
+    expect(map2.ownerID(t0)).toBe(123);
+    expect(map2.hasFallout(t1)).toBe(true);
+    expect(map2.hasDefenseBonus(t2)).toBe(true);
+    expect(map2.numTilesWithFallout()).toBe(1);
+  });
+
+  it("resets mutable state", () => {
+    const w = 2;
+    const h = 2;
+    const terrain = new Uint8Array(w * h).fill(1 << 7);
+    const map = new GameMapImpl(w, h, terrain, w * h);
+
+    map.setOwnerID(map.ref(0, 0), 1);
+    map.setFallout(map.ref(1, 0), true);
+    expect(map.numTilesWithFallout()).toBe(1);
+
+    map.resetMutableState();
+    expect(map.ownerID(map.ref(0, 0))).toBe(0);
+    expect(map.hasFallout(map.ref(1, 0))).toBe(false);
+    expect(map.numTilesWithFallout()).toBe(0);
+  });
+});