task: 完成支付宝共享基础（迁移/WechatConfig/PaymentStore/pkg/alipay）

internal/model/payment.go

@@ -17,6 +17,7 @@ type Payment struct {
 	PaymentConfigID   *uint          `gorm:"column:payment_config_id" json:"payment_config_id,omitempty"`
 	PaymentVoucherKey string         `gorm:"column:payment_voucher_key;type:varchar(500)" json:"payment_voucher_key,omitempty"`
 	PaidAt            *time.Time     `gorm:"column:paid_at" json:"paid_at,omitempty"`
+	ExpireAt          *time.Time     `gorm:"column:expire_at" json:"expire_at,omitempty"`
 	CreatedAt         time.Time      `gorm:"column:created_at;not null;default:CURRENT_TIMESTAMP" json:"created_at"`
 	UpdatedAt         time.Time      `gorm:"column:updated_at;not null;default:CURRENT_TIMESTAMP" json:"updated_at"`
 	DeletedAt         gorm.DeletedAt `gorm:"column:deleted_at;index" json:"deleted_at,omitempty"`