feat: 实现数据库迁移、搜索和分页功能

- 添加数据库迁移系统和初始用户表迁移
- 实现搜索功能模块和API
- 实现分页功能支持
- 添加相关测试文件
- 更新项目配置和文档

tests/migration_tests.rs

@@ -0,0 +1,88 @@
+//! 迁移系统测试
+
+use rust_user_api::storage::{database::DatabaseUserStore, MigrationManager, UserStore};
+use tempfile::tempdir;
+
+#[tokio::test]
+async fn test_migration_system_integration() {
+    // 创建临时数据库
+    let temp_dir = tempdir().expect("Failed to create temp directory");
+    let db_path = temp_dir.path().join("migration_test.db");
+    let database_url = format!("sqlite://{}?mode=rwc", db_path.display());
+    
+    // 创建数据库存储（这会自动运行迁移）
+    let store = DatabaseUserStore::from_url(&database_url)
+        .await
+        .expect("Failed to create database store with migrations");
+    
+    // 验证迁移系统创建了正确的表结构
+    // 通过尝试创建用户来验证表结构正确
+    let user = rust_user_api::models::user::User {
+        id: uuid::Uuid::new_v4(),
+        username: "migration_test_user".to_string(),
+        email: "migration_test@example.com".to_string(),
+        password_hash: "hashed_password".to_string(),
+        created_at: chrono::Utc::now(),
+        updated_at: chrono::Utc::now(),
+    };
+    
+    let result = store.create_user(user).await;
+    assert!(result.is_ok(), "Failed to create user with migrated database: {:?}", result.err());
+    
+    println!("✅ 迁移系统集成测试通过");
+}
+
+#[tokio::test]
+async fn test_migration_manager_directly() {
+    use sqlx::SqlitePool;
+    
+    // 创建内存数据库
+    let pool = SqlitePool::connect("sqlite::memory:")
+        .await
+        .expect("Failed to create test pool");
+    
+    let migration_manager = MigrationManager::new(pool.clone());
+    
+    // 运行迁移
+    let result = migration_manager.run_migrations().await;
+    assert!(result.is_ok(), "Failed to run migrations: {:?}", result.err());
+    
+    // 检查当前版本
+    let version = migration_manager.get_current_version().await.unwrap();
+    assert!(version.is_some(), "No migration version found");
+    assert_eq!(version.unwrap(), 1, "Expected migration version 1");
+    
+    // 检查迁移状态
+    let status = migration_manager.get_migration_status().await.unwrap();
+    assert_eq!(status.len(), 1, "Expected 1 executed migration");
+    assert_eq!(status[0].0, 1, "Expected migration version 1");
+    assert_eq!(status[0].1, "initial_users_table", "Expected migration name");
+    
+    println!("✅ 迁移管理器直接测试通过");
+}
+
+#[tokio::test]
+async fn test_migration_idempotency() {
+    use sqlx::SqlitePool;
+    
+    // 创建内存数据库
+    let pool = SqlitePool::connect("sqlite::memory:")
+        .await
+        .expect("Failed to create test pool");
+    
+    let migration_manager = MigrationManager::new(pool.clone());
+    
+    // 第一次运行迁移
+    let result1 = migration_manager.run_migrations().await;
+    assert!(result1.is_ok(), "First migration run failed: {:?}", result1.err());
+    
+    // 第二次运行迁移（应该跳过已执行的迁移）
+    let result2 = migration_manager.run_migrations().await;
+    assert!(result2.is_ok(), "Second migration run failed: {:?}", result2.err());
+    
+    // 验证只有一个迁移记录
+    let status = migration_manager.get_migration_status().await.unwrap();
+    assert_eq!(status.len(), 1, "Expected only 1 migration record after multiple runs");
+    
+    println!("✅ 迁移幂等性测试通过");
+}