feat: 初始化 ChatGPT Team 管理后端项目

- 添加用户认证模块 (JWT + 密码管理)
- 添加 ChatGPT 账户管理功能
- 添加卡密管理功能 (创建、批量生成、查询)
- 添加邀请功能
- 配置数据库迁移和路由系统

internal/repository/card_key_repo.go

@@ -0,0 +1,89 @@
+package repository
+
+import (
+	"database/sql"
+
+	"gpt-manager-go/internal/models"
+)
+
+// CardKeyRepository 卡密仓储
+type CardKeyRepository struct {
+	db *sql.DB
+}
+
+// NewCardKeyRepository 创建仓储
+func NewCardKeyRepository(db *sql.DB) *CardKeyRepository {
+	return &CardKeyRepository{db: db}
+}
+
+// FindByKey 根据卡密查找
+func (r *CardKeyRepository) FindByKey(key string) (*models.CardKey, error) {
+	cardKey := &models.CardKey{}
+	err := r.db.QueryRow(`
+		SELECT id, key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at
+		FROM card_keys WHERE key = $1
+	`, key).Scan(
+		&cardKey.ID, &cardKey.Key, &cardKey.MaxUses, &cardKey.UsedCount,
+		&cardKey.ValidityType, &cardKey.ExpiresAt, &cardKey.IsActive,
+		&cardKey.CreatedByID, &cardKey.CreatedAt,
+	)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	return cardKey, err
+}
+
+// IncrementUsedCount 增加使用次数，如果达到最大次数则设为不活跃
+func (r *CardKeyRepository) IncrementUsedCount(id int) error {
+	_, err := r.db.Exec(`
+		UPDATE card_keys 
+		SET used_count = used_count + 1,
+		    is_active = CASE WHEN used_count + 1 >= max_uses THEN false ELSE is_active END
+		WHERE id = $1
+	`, id)
+	return err
+}
+
+// Create 创建卡密
+func (r *CardKeyRepository) Create(cardKey *models.CardKey) error {
+	return r.db.QueryRow(`
+		INSERT INTO card_keys (key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at)
+		VALUES ($1, $2, $3, $4, $5, $6, $7, $8)
+		RETURNING id
+	`,
+		cardKey.Key,
+		cardKey.MaxUses,
+		cardKey.UsedCount,
+		cardKey.ValidityType,
+		cardKey.ExpiresAt,
+		cardKey.IsActive,
+		cardKey.CreatedByID,
+		cardKey.CreatedAt,
+	).Scan(&cardKey.ID)
+}
+
+// FindAll 获取所有卡密
+func (r *CardKeyRepository) FindAll() ([]*models.CardKey, error) {
+	rows, err := r.db.Query(`
+		SELECT id, key, max_uses, used_count, validity_type, expires_at, is_active, created_by_id, created_at
+		FROM card_keys ORDER BY created_at DESC
+	`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var cardKeys []*models.CardKey
+	for rows.Next() {
+		ck := &models.CardKey{}
+		if err := rows.Scan(
+			&ck.ID, &ck.Key, &ck.MaxUses, &ck.UsedCount,
+			&ck.ValidityType, &ck.ExpiresAt, &ck.IsActive,
+			&ck.CreatedByID, &ck.CreatedAt,
+		); err != nil {
+			return nil, err
+		}
+		cardKeys = append(cardKeys, ck)
+	}
+	return cardKeys, nil
+}