feat(biji-houdaun): 实现用户注册、登录、 Markdown 文件和图片上传功能

- 新增用户注册、登录接口及服务实现
- 添加 Markdown 文件创建、更新接口及服务实现
- 实现图片上传、获取接口及服务实现
- 集成 Snowflake ID 生成器
- 添加全局异常处理和统一返回结果封装
- 配置跨域访问和静态资源处理
- 实现基础的 XSS 防护

sql/data.sql

@@ -0,0 +1,36 @@
+-- 用户表
+CREATE TABLE IF NOT EXISTS user (
+                                    id INTEGER PRIMARY KEY AUTOINCREMENT,
+                                    username TEXT NOT NULL UNIQUE,
+                                    password TEXT NOT NULL,
+                                    email TEXT,
+                                    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+                                    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+
+-- Markdown文件表
+CREATE TABLE IF NOT EXISTS markdown_file (
+                                             id INTEGER PRIMARY KEY AUTOINCREMENT,
+                                             user_id INTEGER NOT NULL,
+                                             title TEXT NOT NULL,
+                                             file_name TEXT NOT NULL,
+                                             content TEXT NOT NULL,
+                                             created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+                                             updated_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+                                             FOREIGN KEY (user_id) REFERENCES user(id) ON DELETE CASCADE
+    );
+
+-- 图片表
+CREATE TABLE IF NOT EXISTS image (
+                                     id INTEGER PRIMARY KEY AUTOINCREMENT,
+                                     user_id INTEGER NOT NULL,
+                                     markdown_id INTEGER,
+                                     original_name TEXT NOT NULL,
+                                     stored_name TEXT NOT NULL UNIQUE,
+                                     url TEXT NOT NULL,
+                                     size INTEGER NOT NULL,
+                                     content_type TEXT NOT NULL,
+                                     created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+                                     FOREIGN KEY (user_id) REFERENCES user(id) ON DELETE CASCADE,
+    FOREIGN KEY (markdown_id) REFERENCES markdown_file(id) ON DELETE SET NULL
+    );