Provide support to add named configs map for authenticators

[sahandilshan]

Purpose

$subject

With this new support we can define new configurations for Authenticators as below.

# Named configurations
[admin_console.authenticator.mutual_ssl_authenticator.configs.ssl_validation]
CertificateHeader = "X-SSL-CERT"
UsernameHeader = "X-SSL-USER"
ValidateClientCert = true

[Copilot]

Pull Request Overview

This PR adds support for named configuration maps in authenticators, allowing configurations to be organized in named groups rather than just flat parameter maps. This enables more structured configuration management for authenticators while maintaining backward compatibility with existing flat parameter configurations.

Key changes:

• Introduces a nested parameter map structure alongside the existing flat parameter map
• Adds processing logic to handle both named and unnamed configuration elements
• Provides new getter methods to access named configurations

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[madurangasiriwardena]

Formatting issue

[madurangasiriwardena]

It unclear what are we trying to achieve here.

[sahandilshan]

Currently we can have define as below

<Config>
        <Parameter name="name01">value01</Parameter>
        <Parameter name="name02">value02</Parameter>
</Config>

With this new config we are providing the support to define named config along with the previous support. so now we can have something like this

<Config>
        <Parameter name="name01">value01</Parameter>
        <Parameter name="name02">value02</Parameter>
</Config>

<Config name="configName">
        <Parameter name="name01">value01</Parameter>
        <Parameter name="name02">value02</Parameter>
</Config>

[madurangasiriwardena]

Can we avoid iterating the elements twice?