Add comprehensive documentation for SnapForm features and workflows

- Introduced new guides for Depth Plane, Surface, and animation workflows.
- Added installation instructions and FAQs to assist users in setup and troubleshooting.
- Created a quick-start guide for first-time users to convert images to Depth Planes.
- Documented the process for removing backgrounds from images.
- Established a models and storage section to clarify data management.
- Included a stylesheets file for improved documentation styling.
- Updated mkdocs configuration for better navigation and theme settings.

docs/development.md

@@ -109,6 +109,21 @@ uv run pytest tests/test_addon.py tests/test_manifest.py tests/test_pack.py -v
 uv run python pack.py
 ```
 
+本地预览用户文档：
+
+```bash
+uv run mkdocs serve
+```
+
+构建静态文档或使用 Mike 发布版本化文档：
+
+```bash
+uv run mkdocs build
+uv run mike deploy <version> -p
+uv run mike set-default <version> -p
+```
+
+
 `pack.py` 根据 `blender_manifest.toml` 分别生成 Windows、macOS 和 Linux 扩展包，例如 `dist/SnapForm.v0.12.14.windows-x64.zip`。更换 `src/snapform/wheels/` 中随扩展分发的 wheel 后，先刷新锁文件再测试：
 
 ```bash