feat(project): 初始化项目结构和配置

- 添加.gitignore和.flaskenv环境配置文件
- 创建Flask应用基础架构，包括models、services、utils模块
- 配置数据库模型User和Setting，集成SQLAlchemy和Alembic迁移
- 添加前端Vue项目结构，包含Element Plus组件库
- 配置前后端API路由和蓝prints模块
- 实现书籍下载服务BookService功能模块
- 添加代码规范配置.editorconfig、.oxfmtrc.json、.oxlintrc.json
- 配置VSCode推荐插件和前端构建工具链
- 实现文件服务FileService和相关业务逻辑

flask-ui/tsconfig.app.json

@@ -0,0 +1,18 @@
+{
+  "extends": "@vue/tsconfig/tsconfig.dom.json",
+  "include": ["env.d.ts", "src/**/*", "src/**/*.vue"],
+  "exclude": ["src/**/__tests__/*"],
+  "compilerOptions": {
+    // Extra safety for array and object lookups, but may have false positives.
+    "noUncheckedIndexedAccess": true,
+
+    // Path mapping for cleaner imports.
+    "paths": {
+      "@/*": ["./src/*"]
+    },
+
+    // `vue-tsc --build` produces a .tsbuildinfo file for incremental type-checking.
+    // Specified here to keep it out of the root directory.
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo"
+  }
+}