📦 添加虚拟环境和启动脚本

新增:
- backend/venv/ - Python 虚拟环境
- backend/start.sh - 启动脚本（使用虚拟环境）
- backend/requirements.txt - 依赖列表
- .gitignore - 忽略虚拟环境和缓存文件

说明:
- 每个项目使用独立虚拟环境
- 避免依赖冲突
- 启动脚本自动创建和激活虚拟环境

frontend/node_modules/reusify/.github/workflows/ci.yml

@@ -0,0 +1,96 @@
+name: ci
+
+on: [push, pull_request]
+
+jobs:
+  legacy:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: ['0.10', '0.12', 4.x, 6.x, 8.x, 10.x, 12.x, 13.x, 14.x, 15.x, 16.x]
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      - name: Install
+        run: |
+          npm install --production && npm install tape
+
+      - name: Run tests
+        run: |
+          npm run test
+
+  test:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [18.x, 20.x, 22.x]
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      - name: Install
+        run: |
+          npm install
+
+      - name: Run tests
+        run: |
+          npm run test:coverage
+
+  types:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+
+      - name: Install
+        run: |
+          npm install
+
+      - name: Run types tests
+        run: |
+          npm run test:typescript
+
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+
+      - name: Install
+        run: |
+          npm install
+
+      - name: Lint
+        run: |
+          npm run lint