Persist custom world asset configs in runtime snapshots

src/services/runtimeStoryService.ts

@@ -168,6 +168,45 @@ export function buildStoryMomentFromRuntimeOptions(params: {
   } satisfies StoryMoment;
 }
 
+function shouldPreferSnapshotStory(story: StoryMoment | null) {
+  return Boolean(
+    story &&
+      (
+        story.displayMode === 'dialogue' ||
+        story.deferredOptions?.length ||
+        story.dialogue?.length
+      ),
+  );
+}
+
+export function resolveRuntimeStoryMoment(params: {
+  response: RuntimeStoryResponse;
+  hydratedSnapshot: HydratedSavedGameSnapshot;
+  fallbackGameState?: Pick<GameState, 'currentEncounter'>;
+  fallbackStoryText?: string;
+}) {
+  if (shouldPreferSnapshotStory(params.hydratedSnapshot.currentStory)) {
+    return params.hydratedSnapshot.currentStory!;
+  }
+
+  const options =
+    params.response.viewModel.availableOptions.length > 0
+      ? params.response.viewModel.availableOptions
+      : params.response.presentation.options;
+
+  return buildStoryMomentFromRuntimeOptions({
+    storyText:
+      params.response.presentation.storyText ||
+      params.hydratedSnapshot.currentStory?.text ||
+      params.fallbackStoryText ||
+      '',
+    options,
+    gameState: params.hydratedSnapshot.gameState.currentEncounter
+      ? params.hydratedSnapshot.gameState
+      : params.fallbackGameState,
+  });
+}
+
 export async function getRuntimeStoryState(
   sessionId: string,
   options: RuntimeStoryServiceOptions = {},