fix: 优化架构

engine/adapters/llm/mock_adapter.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+from typing import Any
+
+from engine.types import Scene
+
+from .base import BaseLLM
+
+
+class MockLLM(BaseLLM):
+    def generate_script(self, prompt: str, context: dict[str, Any] | None = None) -> list[Scene]:
+        # Simple deterministic scenes for offline development.
+        prompt = (prompt or "").strip()
+        if not prompt:
+            prompt = "a warm city night"
+        return [
+            Scene(image_prompt=f"{prompt}，城市夜景，霓虹灯，电影感", video_motion="缓慢推进镜头，轻微摇镜", narration="夜色温柔落在街灯上"),
+            Scene(image_prompt=f"{prompt}，咖啡店窗边，暖光，细雨", video_motion="侧向平移，人物轻轻抬头", narration="雨声里藏着一段回忆"),
+            Scene(image_prompt=f"{prompt}，桥上远景，车流光轨，温暖", video_motion="拉远全景，光轨流动", narration="我们在光里学会告别"),
+        ]
+
+    def refine_scene(self, scene: Scene, context: dict[str, Any] | None = None) -> Scene:
+        # Minimal polish: append a hint.
+        return Scene(image_prompt=scene.image_prompt, video_motion=scene.video_motion, narration=(scene.narration + "（更凝练）")[:30])
+