Implement drush commands to create clients

Problem/Motivation

There is currently no way to create OpenID Connect clients programmatically through Drush commands. This makes it difficult to automate the creation and management of OpenID Connect clients, especially in deployment scenarios or when working with multiple environments.

Steps to reproduce

Install the OpenID Connect module
Try to create a new OpenID Connect client using Drush
Notice that there are no available commands to manage OpenID Connect clients

Proposed resolution

Add new Drush commands to the OpenID Connect module that allow users to:
List available OpenID Connect client plugins (openid-connect:list-plugins, oidc-lp)
Create new OpenID Connect clients (openid-connect:create-client, oidc-cc)
List existing OpenID Connect clients (openid-connect:list-clients, oidc-lc)
The implementation includes support for different client types (Generic, Google, Facebook, Okta) with their specific configuration options.

Remaining tasks

[x] Implement basic Drush command structure
[x] Add command to list available plugins
[x] Add command to create clients with plugin-specific settings
[x] Add command to list existing clients
[ ] Add unit tests
[x] Add documentation
[ ] Add validation for plugin-specific required fields
[ ] Add command to delete clients
[ ] Add command to update existing clients

User interface changes

No UI changes. This feature adds command-line interface capabilities only.

API changes

New Drush commands added:
openid-connect:list-plugins (alias: oidc-lp)
openid-connect:create-client (alias: oidc-cc)
openid-connect:list-clients (alias: oidc-lc)

Data model changes

No changes to the existing data model. The implementation uses the existing OpenID Connect client configuration entity structure.
The commands follow Drupal's coding standards and best practices, utilizing dependency injection and proper error handling. They provide a robust way to manage OpenID Connect clients through the command line interface.