fix: scim use first email or phone if no primary is set (#9236)

# Which Problems Are Solved
- scim v2 only maps the primary phone/email to the zitadel user, this
does not work if no primary is set

# How the Problems Are Solved
- the first phone / email is mapped if no primary is available

# Additional Context
Part of #8140

Co-authored-by: Stefan Benz <46600784+stebenz@users.noreply.github.com>

internal/api/scim/resources/user_mapping.go

@@ -154,6 +154,15 @@ func (h *UsersHandler) mapPrimaryEmail(scimUser *ScimUser) (command.Email, error
 		}, nil
 	}
 
+	// if no primary email was found, the first email will be used
+	for _, email := range scimUser.Emails {
+		email.Primary = true
+		return command.Email{
+			Address:  domain.EmailAddress(email.Value),
+			Verified: h.config.EmailVerified,
+		}, nil
+	}
+
 	return command.Email{}, zerrors.ThrowInvalidArgument(nil, "SCIM-EM19", "Errors.User.Email.Empty")
 }
 
@@ -169,6 +178,15 @@ func (h *UsersHandler) mapPrimaryPhone(scimUser *ScimUser) *command.Phone {
 		}
 	}
 
+	// if no primary phone was found, the first phone will be used
+	for _, phone := range scimUser.PhoneNumbers {
+		phone.Primary = true
+		return &command.Phone{
+			Number:   domain.PhoneNumber(phone.Value),
+			Verified: h.config.PhoneVerified,
+		}
+	}
+
 	return nil
 }