.Net: Endpoint and API key identification heuristic for AzureOpenAI services

[SergeyMenshykh]

Consider porting the same endpoint and API key identification heuristic, recently added to the new OpenAI.ClientCore class, to the AzureOpenAI.ClientCore:

internal ClientCore(
    string modelId,
    string? apiKey = null,
    string? organizationId = null,
    Uri? endpoint = null,
    HttpClient? httpClient = null,
    ILogger? logger = null)
{
    Verify.NotNullOrWhiteSpace(modelId);

    this.Logger = logger ?? NullLogger.Instance;
    this.ModelId = modelId;

    this.AddAttribute(AIServiceExtensions.ModelIdKey, modelId);

    // Accepts the endpoint if provided, otherwise uses the default OpenAI endpoint.
    this.Endpoint = endpoint ?? httpClient?.BaseAddress;
    if (this.Endpoint is null)
    {
        Verify.NotNullOrWhiteSpace(apiKey); // For Public OpenAI Endpoint a key must be provided.
        this.Endpoint = new Uri(OpenAIV1Endpoint);
    }
    else if (string.IsNullOrEmpty(apiKey))
    {
        // Avoids an exception from OpenAI Client when a custom endpoint is provided without an API key.
        apiKey = SingleSpace;
    }

    this.AddAttribute(AIServiceExtensions.EndpointKey, this.Endpoint.ToString());

    var options = GetOpenAIClientOptions(httpClient, this.Endpoint);
    if (!string.IsNullOrWhiteSpace(organizationId))
    {
        options.AddPolicy(CreateRequestHeaderPolicy("OpenAI-Organization", organizationId!), PipelinePosition.PerCall);

        this.AddAttribute(ClientCore.OrganizationKey, organizationId);
    }

    this.Client = new OpenAIClient(apiKey!, options);
}

Related comment - #7060 (comment)