feat: 纳入 VeighNa 4.4.0 上游源码作为版本参考

- 添加 vnpy_v4.4.0/ 目录到版本控制
- 删除嵌入的 .git 目录避免嵌套仓库
- 添加 README_SANGUO.md 说明来源和用途
- 更新 .gitignore 移除 vnpy_v4.4.0/ 忽略规则

上游代码信息:
- 项目: VeighNa 量化交易平台
- 版本: 4.4.0
- 来源: https://github.com/vnpy/vnpy

用途: 版本参考、代码学习、差异对比、离线开发

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

vnpy_v4.4.0/.github/workflows/pythonapp.yml

@@ -0,0 +1,41 @@
+name: Python application
+
+on:
+  push:
+    branches: [master, dev]
+  pull_request:
+    branches: [master, dev]
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.13"
+          cache: pip
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install ruff mypy uv types-tqdm
+          uv pip install ta-lib==0.6.4 --index=https://pypi.vnpy.com --system
+          uv pip install -e .[alpha,dev] --system
+
+      - name: Lint
+        run: ruff check .
+
+      - name: Type check
+        run: mypy vnpy
+
+      - name: Build
+        run: uv build