feat: make demo story screen interactive

src/app/turnAdapter.spec.ts

@@ -0,0 +1,39 @@
+import { describe, expect, it } from "vitest";
+
+import initialView from "../../fixtures/player-view/initial.json";
+import type { PlayerView, TurnRequest } from "@contracts";
+
+import { submitDemoTurn } from "./turnAdapter";
+
+function request(intent: TurnRequest["intent"], input: string): TurnRequest {
+  return {
+    storyId: initialView.storyId,
+    branchId: initialView.branchId,
+    expectedNodeId: initialView.nodeId,
+    actionId: `test_${intent}`,
+    intent,
+    input
+  };
+}
+
+describe("local turn adapter", () => {
+  it("preserves literal player input without inventing additional player speech", async () => {
+    const literalInput = "我把手电筒放在长椅上。";
+    const result = await submitDemoTurn(
+      request("speak_or_act", literalInput),
+      initialView as PlayerView
+    );
+    const playerBeats = result.playerView.beats.filter((beat) => beat.speaker === "你");
+
+    expect(playerBeats).toHaveLength(1);
+    expect(playerBeats[0]?.text).toBe(literalInput);
+  });
+
+  it("accepts an empty Continue intent without creating a player beat", async () => {
+    const result = await submitDemoTurn(request("continue", ""), initialView as PlayerView);
+
+    expect(result.committedNodeId).toBe("node_002");
+    expect(result.playerView.beats.some((beat) => beat.speaker === "你")).toBe(false);
+    expect(result.playerView.beats.at(-1)?.speaker).toBe("娜娜");
+  });
+});