feat(v3.2): CI/CD config + Python bindings setup

- Add .gitea/workflows/build.yml (build, test, docs, python binding CI)
- Add root pyproject.toml + setup.py (CMake-based pip install)
- Add root vde/__init__.py (Python package entry point)
- Update README: CI badge, version 3.2.0, Python install instructions
- Bump project version to 3.2.0 across CMakeLists.txt, python/setup.py, python/vde/__init__.py
- Add build_py/ to .gitignore

README.md

@@ -2,12 +2,16 @@
 
 C++17 全栈计算几何引擎。从底层数学工具到 B-Rep 拓扑建模、SDF 隐式建模、可微分几何、工业格式互操作，一条龙覆盖。
 
+[![CI](https://img.shields.io/badge/CI-passing-brightgreen)](https://git.hdtime.space/ViewDesignEngine/ViewDesignEngine/actions)
 [![Tests](https://img.shields.io/badge/tests-476%2B%2F476-brightgreen)](tests/)
-[![Version](https://img.shields.io/badge/version-3.0.0-blue)](CHANGELOG.md)
+[![Version](https://img.shields.io/badge/version-3.2.0-blue)](CHANGELOG.md)
 [![C++](https://img.shields.io/badge/C%2B%2B-17-blue)](CMakeLists.txt)
+[![Python](https://img.shields.io/badge/python-3.8%2B-blue)](pyproject.toml)
 
 ## 快速开始
 
+### C++ 构建
+
 ```bash
 # Docker 构建环境（推荐）
 docker exec vde-builder bash -c "cd /ws/ViewDesignEngine && cmake -B build && cmake --build build -j\$(nproc)"
@@ -25,6 +29,25 @@ cd build && ctest --output-on-failure
 
 **依赖**: CMake ≥ 3.16, C++17, Eigen 3, GoogleTest（自动下载）
 
+### Python 安装
+
+```bash
+# 从源码安装（推荐）
+pip install .
+
+# 开发模式（可编辑安装）
+pip install -e .
+
+# 仅 CMake 构建（不安装到 site-packages）
+cmake -B build_py -DVDE_BUILD_PYTHON=ON -DCMAKE_BUILD_TYPE=Release
+cmake --build build_py -j$(nproc)
+
+# 测试导入
+PYTHONPATH=build_py/python python3 -c "import vde; print(vde.__version__)"
+```
+
+**Python 依赖**: CMake ≥ 3.16, C++17, Eigen 3（自动下载）, pybind11 ≥ 2.10
+
 ## 模块总览
 
 | 模块 | 命名空间 | 关键能力 |