feat(global): 常驻场景循环播放全局 BGM；Sound 支持 loop/volume

- 移除 init 与各场景对 my-sound 的误停，避免打断 BGM
- BGM 资源路径 public/bg.mp3（需自行放置文件）

Made-with: Cursor

src/init.ts

@@ -6,7 +6,6 @@ import { SceneType } from "./enums/SceneType";
 import { assetManager } from "./core/AssetManager";
 import { logger } from "./core/Logger";
 import eventBus from "./core/EventBus";
-import soundManager from "./utils/Sound";
 import { Container } from "pixi.js";
 
 const game = Game.getInstance();
@@ -18,8 +17,6 @@ export async function initApp(): Promise<void> {
   await assetManager.init();
   await game.init();
 
-  soundManager.add("my-sound", "/bg.mp3", { singleInstance: true, autoPlay: false });
-
   const sceneModules = import.meta.glob("./stages/**/page_*.ts", { eager: true });
 
   for (const path in sceneModules) {

src/stages/_global/page_00_global.ts

@@ -1,8 +1,13 @@
 import { logger } from "@/core/Logger";
 import { SceneType } from "@/enums/SceneType";
 import { BaseScene } from "@/scene/BaseScene";
+import soundManager from "@/utils/Sound";
 import { Assets, Container } from "pixi.js";
 
+/** 全局循环 BGM，与业务音效分开命名，避免切场景时被误停 */
+const GLOBAL_BGM_ALIAS = "global-bgm";
+const GLOBAL_BGM_URL = "/bg.mp3";
+
 export default class Global extends BaseScene {
   stage: Container = new Container();
 
@@ -16,6 +21,15 @@ export default class Global extends BaseScene {
     Assets.add({ alias: "btn-bg-press", src: "/assets/images/button_square_depth_gradient.png" });
     await Assets.load("btn-bga");
     await Assets.load("btn-bg-press");
+
+    if (!soundManager.exists(GLOBAL_BGM_ALIAS)) {
+      soundManager.add(GLOBAL_BGM_ALIAS, GLOBAL_BGM_URL, {
+        singleInstance: true,
+        loop: true,
+        autoPlay: false,
+        volume: 0.4,
+      });
+    }
   }
 
   async layout(): Promise<void> {
@@ -37,8 +51,10 @@ export default class Global extends BaseScene {
 
   onLoad(): void {
     logger.info("Resident scene 00_global onLoad");
+    soundManager.play(GLOBAL_BGM_ALIAS, { loop: true, volume: 0.4 });
   }
 
   onUnLoad(): void {
+    soundManager.stop(GLOBAL_BGM_ALIAS);
   }
 }

src/stages/page_init.ts

@@ -4,7 +4,6 @@ import Game from "@/core/Game";
 import { BaseScene } from "@/scene/BaseScene";
 import { SceneType } from "@/enums/SceneType";
 import position from "@/utils/Position";
-import soundManager from "@/utils/Sound";
 import {
   AnimatedSprite,
   Container,
@@ -55,6 +54,8 @@ export default class InitScene extends BaseScene {
       this.loadingBtn!.textObj.text =
         progress >= 1 ? "即将就绪" : `加载中 ${Math.round(progress * 100)}%`;
     });
+    // 延迟3秒
+    await new Promise(resolve => setTimeout(resolve, 3000));
 
     if (bundle) {
       this.assets = bundle as unknown as Record<string, Texture>;
@@ -159,7 +160,6 @@ export default class InitScene extends BaseScene {
 
   onUnLoad(): void {
     window.removeEventListener("resize", this.onResize);
-    soundManager.stop("my-sound");
   }
 
   update(_dt: number, _name: string, ticker: Ticker): void {

src/stages/welcome/page_welcome.ts

@@ -1,5 +1,4 @@
 import Button from "@/components/Button";
-import soundManager from "@/utils/Sound";
 import { Container } from "pixi.js";
 import { BaseScene } from "@/scene/BaseScene";
 import { SceneType } from "@/enums/SceneType";
@@ -29,7 +28,6 @@ export default class WelcomeScene extends BaseScene {
   }
 
   onUnLoad(): void {
-    soundManager.stop("my-sound");
     console.log("welcome onUnLoad");
   }
 }

src/utils/Sound.ts

@@ -9,18 +9,29 @@ class SoundManager {
     sound.volumeAll = this.volume;
   }
 
-  add(name: string, url: string, options?: { singleInstance?: boolean; autoPlay?: boolean }): void {
+  add(
+    name: string,
+    url: string,
+    options?: {
+      singleInstance?: boolean;
+      autoPlay?: boolean;
+      loop?: boolean;
+      volume?: number;
+    }
+  ): void {
     sound.add(name, {
       url,
       singleInstance: options?.singleInstance ?? true,
       autoPlay: options?.autoPlay ?? false,
+      loop: options?.loop ?? false,
+      volume: options?.volume ?? 1,
     });
     logger.debug(`Sound: added "${name}"`);
   }
 
-  play(name: string): void {
+  play(name: string, playOptions?: { loop?: boolean; volume?: number }): void {
     if (this.muted) return;
-    sound.play(name);
+    sound.play(name, playOptions);
   }
 
   stop(name: string): void {