docs: fix doc api

docs/boardgame-core-guide.md

@@ -624,19 +624,36 @@ roll(dice, rng);                // 使用 RNG 掷骰子
 
 ```ts
 import { createGameContextFromModule } from 'boardgame-core';
-import { ReactiveScene } from 'boardgame-phaser';
+import { ReactiveScene, bindRegion, bindSignal } from 'boardgame-phaser';
 import * as ticTacToe from './tic-tac-toe';
 
-class TicTacToeScene extends ReactiveScene<typeof ticTacToe.createInitialState> {
+type GameState = ReturnType<typeof ticTacToe.createInitialState>;
+
+class TicTacToeScene extends ReactiveScene<GameState> {
     protected onStateReady() {
         // 初始化 Phaser 对象
     }
 
     protected setupBindings() {
-        // 绑定信号到 Phaser 对象
-        bindSignal(this, () => this.gameContext.state.value.winner, (winner) => {
+        // 绑定简单信号值
+        bindSignal(this.gameContext.state, state => state.winner, winner => {
             if (winner) this.showWinMessage(winner);
         });
+
+        // 绑定区域（响应 parts 数组变化）
+        bindRegion(
+            this.gameContext.state,
+            state => state.parts,
+            this.gameContext.state.value.board,
+            {
+                cellSize: { x: 100, y: 100 },
+                offset: { x: 50, y: 50 },
+                factory: (part, pos) => {
+                    return this.add.text(pos.x, pos.y, part.player);
+                },
+            },
+            this.boardContainer,
+        );
     }
 }
 
@@ -644,3 +661,10 @@ class TicTacToeScene extends ReactiveScene<typeof ticTacToe.createInitialState>
 const gameContext = createGameContextFromModule(ticTacToe);
 const scene = new TicTacToeScene(gameContext);
 ```
+
+**bindRegion 参数说明：**
+- `state` — MutableSignal 游戏状态
+- `state => state.parts` — 获取 parts 数组的 getter（effect 会追踪此依赖）
+- `region` — Region 对象
+- `options` — 配置项（cellSize, offset, factory）
+- `container` — Phaser 容器