fix: prevent error reason leakage in case of IgnoreUnknownUsernames (#8372)

# Which Problems Are Solved

ZITADEL administrators can enable a setting called "Ignoring unknown
usernames" which helps mitigate attacks that try to guess/enumerate
usernames. If enabled, ZITADEL will show the password prompt even if the
user doesn't exist and report "Username or Password invalid".
Due to a implementation change to prevent deadlocks calling the
database, the flag would not be correctly respected in all cases and an
attacker would gain information if an account exist within ZITADEL,
since the error message shows "object not found" instead of the generic
error message.

# How the Problems Are Solved

- Proper check of the error using an error function / type and
`errors.Is`

# Additional Changes

None.

# Additional Context

- raised in a support request

Co-authored-by: Silvan <silvan.reusser@gmail.com>

internal/user/repository/view/user_view.go

@@ -16,12 +16,12 @@ import (
 //go:embed user_by_id.sql
 var userByIDQuery string
 
-func UserByID(db *gorm.DB, table, userID, instanceID string) (*model.UserView, error) {
+func UserByID(ctx context.Context, db *gorm.DB, userID, instanceID string) (*model.UserView, error) {
 	user := new(model.UserView)
 
 	query := db.Raw(userByIDQuery, instanceID, userID)
 
-	tx := query.BeginTx(context.Background(), &sql.TxOptions{ReadOnly: true})
+	tx := query.BeginTx(ctx, &sql.TxOptions{ReadOnly: true})
 	defer func() {
 		if err := tx.Commit().Error; err != nil {
 			logging.OnError(err).Info("commit failed")
@@ -35,8 +35,8 @@ func UserByID(db *gorm.DB, table, userID, instanceID string) (*model.UserView, e
 		return user, nil
 	}
 	if errors.Is(err, gorm.ErrRecordNotFound) {
-		return nil, zerrors.ThrowNotFound(err, "VIEW-hodc6", "object not found")
+		return nil, zerrors.ThrowNotFound(err, "VIEW-hodc6", "Errors.User.NotFound")
 	}
-	logging.WithFields("table ", table).WithError(err).Warn("get from cache error")
-	return nil, zerrors.ThrowInternal(err, "VIEW-qJBg9", "cache error")
+	logging.WithError(err).Warn("unable to get user by id")
+	return nil, zerrors.ThrowInternal(err, "VIEW-qJBg9", "unable to get user by id")
 }