Implement a component-level test using `WidgetTester` to verify UI rendering and user interactions (tapping, scrolling, entering text). Use when validating that a specific widget displays correct data and responds to events as expected.

Adds interactive widget previews to the project using the previews.dart system. Use when creating new UI components or updating existing screens to ensure consistent design and interactive testing.

DSH 桌面宠物：一行命令装好即用的透明动画小桌宠，支持多开、大小位置随心配置；还内置 DIY 素材链，能用 AI 视频自造专属宠物

🐋 DeepSeek 娘桌宠：住进 DeepSeek Harness Web 界面的蓝发鲸鱼女仆。工作链路（开工/轮播/收工庆祝）、任务完成统计气泡（用时/消耗/花费）、会话与单轮费用 pill（缓存命中/未命中/输出三桶 + 谷峰）、📊 分时段花费看板（北京小时·日趋势、三桶堆叠柱、缓存命中率、可拖动缩放）、睡眠系统、时间感知、余额/天气/喂食按钮与完整设置面板。A whale-girl desktop pet for the DeepSeek Harness Web UI.

PyWry is a cross-platform app factory, rendering engine and UI toolkit for Python that produces native desktop, web, and notebook experiences from a single API.