Add support for dependency injection's IHttpClientFactory.

[AhmedZaki99]

Picking up from #54 (Closes #54)

Changes:

1. Added a constructor overload for TodoistRestClient that takes an HttpClient instance as an argument:

public TodoistRestClient(string token, HttpClient httpClient)
{
    _httpClient = httpClient;

    _httpClient.BaseAddress = new Uri("https://api.todoist.com/sync/v9/");
    if (!string.IsNullOrEmpty(token))
    {
        _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
    }
}

2. Created an ITodoistClientFactory interface and TodoistClientFactory implementation to inject into the DI container, and use the provided IHttpClientFactory:

public interface ITodoistClientFactory
{
    TodoistClient CreateClient(string token);
}

internal sealed class TodoistClientFactory : ITodoistClientFactory
{
    private readonly IHttpClientFactory _httpClientFactory;

    public TodoistClientFactory(IHttpClientFactory httpClientFactory)
    {
        _httpClientFactory = httpClientFactory;
    }

    public TodoistClient CreateClient(string token)
    {
        var httpClient = _httpClientFactory.CreateClient();
        var todoistRestClient = new TodoistRestClient(token, httpClient);

        return new TodoistClient(todoistRestClient);
    }
}

3. Added an extension method to inject both the ITodoistClientFactory and IHttpClientFactory:

public static class TodoistServiceCollectionExtensions
{
    public static IServiceCollection AddTodoistClient(this IServiceCollection services)
    {
        services.AddHttpClient();
        services.AddSingleton<ITodoistClientFactory, TodoistClientFactory>();

        return services;
    }
}

[olsh]

I recommend including the dependency only for the .NET Core version of the library. There's no need to include it for the full framework. Additionally, we should consider lowering the version to the oldest LTS - 6.x.

[AhmedZaki99]

Done 👍

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[olsh]

Thank you!