feat: 添加 Docker 部署支持和多 OCR 提供商架构

- 添加完整的 Docker 配置 (Dockerfile, docker-compose.yml)
- 修复前端硬编码端口 4000，改用相对路径 /api
- 实现多 OCR 提供商架构 (Tesseract.js/Baidu/RapidOCR)
- 修复 Docker 环境中图片上传路径问题
- 添加用户设置页面和 AI 分析服务
- 更新 Prisma schema 支持 AI 分析结果
- 添加部署文档和 OCR 配置指南

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/Dockerfile

@@ -0,0 +1,42 @@
+# ========================================
+# Stage 1: Dependencies
+# ========================================
+FROM node:20-alpine AS deps
+
+WORKDIR /app
+
+# Copy package files
+COPY package*.json ./
+
+# Install dependencies
+RUN npm ci
+
+# ========================================
+# Stage 2: Builder
+# ========================================
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+COPY --from=deps /app/node_modules ./node_modules
+COPY . .
+
+# Build the application (skip type check for production)
+RUN npx vite build
+
+# ========================================
+# Stage 3: Runner with Nginx
+# ========================================
+FROM nginx:alpine AS runner
+
+# Copy built assets from builder
+COPY --from=builder /app/dist /usr/share/nginx/html
+
+# Copy custom nginx config
+COPY nginx.docker.conf /etc/nginx/conf.d/default.conf
+
+# Expose port
+EXPOSE 80
+
+# Start nginx
+CMD ["nginx", "-g", "daemon off;"]