refactor(0.1.14-P2): Kernel 三合一 + GameEngine 引擎门面

- Kernel（engine/kernel/Kernel.ts）：游戏时钟+种子随机+事件总线——单一实例三合一，
  World 不再自造 clock/rng（内核注入，bus 透传 out）
- GameEngine（engine/GameEngine.ts）：唯一引擎入口——
  new GameEngine({seed,datapack}) → world/facade/kernel/datapack，
  advance/act/query/subscribe/about/installPlugin/snapshot/restore/status
- World 构造接受 kernel 注入（保持行为等价：时钟注册顺序不变）
- ApiFacade.subscribe 简化纯实现
- 验证：967 测试全绿、金钟罩三档零漂移、typecheck 0 error

src/renderer/game/engine/runtime/ApiFacade.ts

@@ -115,6 +115,7 @@ export class GameFacade {
     }
   }
 
+
   subscribe(on: (e: FacadeEvent) => void): () => void {
     const bus: WorldEventBus = {
       onLog: (kind: LogKind, text: string) => on({ type: 'log', kind, text, year: this.world.state.year, month: this.world.state.month }),