feat: add extraction_service (PDF/Docx/Txt) and update .gitignore to exclude venv

extraction_service/install.bat

@@ -0,0 +1,89 @@
+@echo off
+chcp 65001 >nul
+echo ================================
+echo 安装文档提取微服务依赖
+echo ================================
+echo.
+
+REM 检查Python
+echo [1/5] 检查Python环境...
+python --version >nul 2>&1
+if errorlevel 1 (
+    echo ❌ 错误: 未找到Python
+    echo 请先安装Python 3.8或更高版本
+    echo 下载地址: https://www.python.org/downloads/
+    pause
+    exit /b 1
+)
+
+python --version
+echo ✅ Python已安装
+echo.
+
+REM 创建虚拟环境
+echo [2/5] 创建虚拟环境...
+if exist venv (
+    echo 虚拟环境已存在，跳过创建
+) else (
+    python -m venv venv
+    if errorlevel 1 (
+        echo ❌ 创建虚拟环境失败
+        pause
+        exit /b 1
+    )
+    echo ✅ 虚拟环境创建成功
+)
+echo.
+
+REM 激活虚拟环境
+echo [3/5] 激活虚拟环境...
+call venv\Scripts\activate
+if errorlevel 1 (
+    echo ❌ 激活虚拟环境失败
+    pause
+    exit /b 1
+)
+echo ✅ 虚拟环境已激活
+echo.
+
+REM 升级pip
+echo [4/5] 升级pip...
+python -m pip install --upgrade pip
+echo.
+
+REM 安装依赖
+echo [5/5] 安装依赖包...
+echo 这可能需要几分钟时间...
+pip install -r requirements.txt
+if errorlevel 1 (
+    echo ❌ 依赖安装失败
+    pause
+    exit /b 1
+)
+echo.
+
+REM 验证安装
+echo ================================
+echo 验证安装
+echo ================================
+python -c "import fastapi; print('✅ FastAPI:', fastapi.__version__)"
+python -c "import fitz; print('✅ PyMuPDF:', fitz.__version__)"
+python -c "import uvicorn; print('✅ Uvicorn: OK')"
+echo.
+
+echo ================================
+echo 🎉 安装完成！
+echo ================================
+echo.
+echo 下一步:
+echo 1. 启动服务: start.bat
+echo 2. 测试服务: python test_service.py
+echo.
+
+pause
+
+
+
+
+
+