add comments, code refactor

pkg/models/two_factor_recovery_code.go

@@ -1,5 +1,6 @@
 package models
 
+// TwoFactorRecoveryCode represents user 2fa recovery codes stored in database
 type TwoFactorRecoveryCode struct {
 	Uid             int64  `xorm:"PK"`
 	RecoveryCode    string `xorm:"VARCHAR(64) PK"`
@@ -8,6 +9,7 @@ type TwoFactorRecoveryCode struct {
 	UsedUnixTime    int64
 }
 
+// TwoFactorRecoveryCodeLoginRequest represents all parameters of 2fa login request via recovery code
 type TwoFactorRecoveryCodeLoginRequest struct {
 	RecoveryCode string `json:"recoveryCode" binding:"required,notBlank,len=11"`
 }