feat: enrich campaign reward and roster visuals

src/game/scenes/StoryScene.ts

@@ -9,7 +9,11 @@ import {
   type BattleUiIconKey
 } from '../data/battleUiIcons';
 import { portraitAssetEntriesForKey, portraitKeyForSpeaker, type PortraitAssetEntry } from '../data/portraitAssets';
-import { storyBackgroundAssets, storyBackgroundKeyForPage } from '../data/storyAssets';
+import {
+  storyBackgroundAssets,
+  storyBackgroundKeyForPage,
+  storyBackgroundKeysForPages
+} from '../data/storyAssets';
 import {
   ensureUnitAnimations,
   loadUnitBaseSheets,
@@ -130,6 +134,7 @@ const firstBattleWarmupUnitTextureKeys = [
 export class StoryScene extends Phaser.Scene {
   private pageIndex = 0;
   private pages: StoryPage[] = prologuePages;
+  private selectedStoryBackgroundKeys = storyBackgroundKeysForPages(prologuePages);
   private nextScene = 'BattleScene';
   private nextSceneData?: Record<string, unknown>;
   private transitioning = false;
@@ -159,6 +164,7 @@ export class StoryScene extends Phaser.Scene {
 
   init(data?: StorySceneData) {
     this.pages = data?.pages?.length ? data.pages : prologuePages;
+    this.selectedStoryBackgroundKeys = storyBackgroundKeysForPages(this.pages);
     this.nextScene = data?.nextScene ?? 'BattleScene';
     this.nextSceneData = data?.nextSceneData;
     this.pageIndex = 0;
@@ -745,7 +751,10 @@ export class StoryScene extends Phaser.Scene {
   }
 
   private pageBackgroundAssetKey(page: StoryPage) {
-    const key = storyBackgroundKeyForPage(page.background, page.id);
+    const pageIndex = this.pages.indexOf(page);
+    const key = pageIndex >= 0
+      ? this.selectedStoryBackgroundKeys[pageIndex]
+      : storyBackgroundKeyForPage(page.background, page.id);
     return storyBackgroundAssets[key] ? key : page.background;
   }