feat(auth): 实现管理员密码修改功能和安全增强

- 添加密码修改API端点，支持当前密码验证和新密码更新
- 将密码存储从环境变量迁移到数据库，使用bcrypt加密
- 新增admin_settings表用于存储密码哈希和系统设置
- 添加密码强度验证和错误处理逻辑
- 更新文档说明密码管理功能和默认凭据

VHDSelectServer/init-db.sql

@@ -40,9 +40,32 @@ VALUES
     ('MACHINE003', TRUE, 'TEST')
 ON CONFLICT (machine_id) DO NOTHING;
 
+-- 创建管理员密码表
+CREATE TABLE IF NOT EXISTS admin_settings (
+    id SERIAL PRIMARY KEY,
+    setting_key VARCHAR(255) UNIQUE NOT NULL,
+    setting_value TEXT NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+-- 为admin_settings表创建更新时间触发器
+DROP TRIGGER IF EXISTS update_admin_settings_updated_at ON admin_settings;
+CREATE TRIGGER update_admin_settings_updated_at
+    BEFORE UPDATE ON admin_settings
+    FOR EACH ROW
+    EXECUTE FUNCTION update_updated_at_column();
+
+-- 插入默认管理员密码 (admin123的bcrypt哈希)
+INSERT INTO admin_settings (setting_key, setting_value) 
+VALUES ('admin_password_hash', '$2a$10$uTXfi1JIapQn08aVZL1mKO9B6jU8GgOmW6bIuMP.pTk/M.pxf86Su')
+ON CONFLICT (setting_key) DO NOTHING;
+
 -- 创建索引以提高查询性能
 CREATE INDEX IF NOT EXISTS idx_machines_machine_id ON machines(machine_id);
 CREATE INDEX IF NOT EXISTS idx_machines_protected ON machines(protected);
+CREATE INDEX IF NOT EXISTS idx_admin_settings_key ON admin_settings(setting_key);
 
 -- 显示表结构
-\d machines;
+\d machines;
+\d admin_settings;