[Bug] Prevent game from hanging when loading in a new battle (#5676)

src/field/pokemon.ts

@@ -840,12 +840,17 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
 
     await Promise.allSettled(loadPromises);
 
-    // Wait for the assets we queued to load to finish loading, then...
+    // This must be initiated before we queue loading, otherwise the load could have finished before
+    // we reach the line of code that adds the listener, causing a deadlock.
+    const waitOnLoadPromise = new Promise<void>(resolve => globalScene.load.once(Phaser.Loader.Events.COMPLETE, resolve));
+
     if (!globalScene.load.isLoading()) {
       globalScene.load.start();
     }
+
+    // Wait for the assets we queued to load to finish loading, then...
     // See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_promises#creating_a_promise_around_an_old_callback_api
-    await new Promise(resolve => globalScene.load.once(Phaser.Loader.Events.COMPLETE, resolve));
+    await waitOnLoadPromise;
 
     // With the sprites loaded, generate the animation frame information
     if (this.isPlayer()) {