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/kernel/Kernel.ts

@@ -0,0 +1,56 @@
+import { GameClock } from './clock'
+import { Rng, seedToRng } from './rng'
+import type { WorldEventBus } from '../runtime/World'
+
+export interface KernelBus {
+  onLog: WorldEventBus['onLog']
+  onChronicle: WorldEventBus['onChronicle']
+  onBattle: WorldEventBus['onBattle']
+  onPendingEvent: WorldEventBus['onPendingEvent']
+  onGameOver: WorldEventBus['onGameOver']
+  onYearPaper?: WorldEventBus['onYearPaper']
+  onSystemChange?: WorldEventBus['onSystemChange']
+  onPluginChange?: WorldEventBus['onPluginChange']
+}
+
+/** 三合一内核：游戏时钟 + 种子随机 + 事件总线（单一实例，由 GameEngine 持有） */
+export class Kernel {
+  readonly clock: GameClock
+  readonly rng: Rng
+  readonly bus: KernelBus
+  private busOut: WorldEventBus[] = []
+
+  constructor(seed: string) {
+    this.clock = new GameClock()
+    this.rng = new Rng(seedToRng(seed))
+    this.bus = {
+      onLog: (kind, text) => this.busOut.forEach((o) => o.onLog(kind, text)),
+      onChronicle: (entry, important) => this.busOut.forEach((o) => o.onChronicle(entry, important)),
+      onBattle: (log) => this.busOut.forEach((o) => o.onBattle(log)),
+      onPendingEvent: (id) => this.busOut.forEach((o) => o.onPendingEvent(id)),
+      onGameOver: (reason, year) => this.busOut.forEach((o) => o.onGameOver(reason, year)),
+      onYearPaper: (r) => this.busOut.forEach((o) => o.onYearPaper?.(r)),
+      onSystemChange: (id, enabled) => this.busOut.forEach((o) => o.onSystemChange?.(id, enabled)),
+      onPluginChange: (id, action) => this.busOut.forEach((o) => o.onPluginChange?.(id, action))
+    }
+  }
+
+  /** 注册外部订阅（每引擎一个 World 共享 bus） */
+  attach(out: WorldEventBus): void {
+    this.busOut.push(out)
+  }
+
+  detachAll(): void {
+    this.busOut = []
+  }
+
+  /** 随机快照回写（存档时） */
+  syncRngTo(state: { rng: ReturnType<Rng['getState']> }): void {
+    state.rng = this.rng.getState()
+  }
+}
+
+/** 引擎启动统一入口（含默认种子） */
+export function makeKernel(seed?: string): Kernel {
+  return new Kernel(seed ?? `cotyc-${Date.now()}-${Math.random().toString(36).slice(2, 8)}`)
+}