feat: add ldap external idp to login api (#5938)

* fix: handling of ldap login through separate endpoint

* fix: handling of ldap login through separate endpoint

* fix: handling of ldap login through separate endpoint

* fix: successful intent for ldap

* fix: successful intent for ldap

* fix: successful intent for ldap

* fix: add changes from code review

* fix: remove set intent credentials and handle ldap errors

* fix: remove set intent credentials and handle ldap errors

* refactor into separate methods and fix merge

* remove mocks

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Co-authored-by: Livio Spring <livio.a@gmail.com>

internal/static/i18n/ja.yaml

@@ -129,6 +129,7 @@ Errors:
       MinimumExternalIDPNeeded: 少なくとも1つのIDPを追加する必要があります
       AlreadyExists: 外部IDPはすでに使用されています
       NotFound: 外部IDPが見つかりません
+      LoginFailed: 外部IDPでのログインに失敗
     MFA:
       OTP:
         AlreadyReady: 多要素OTP（ワンタイムパスワード）は設定済みです