notes for version: v0.31.0 - add extension methods to simplify `FlioxHub` configuration

[friflo]

Simplify

add extension methods to simplify server configuration

public static class HubExtensions
{
    public static void UseClusterDB();
    public static void UseMonitorDB();
    public static void UsePubSub();
    public static async Task UseUserDB();
}

public static class HttpHostExtensions
{
    public static void UseStaticFiles();
}

public static class GraphQLExtensions
{
    public static void UseGraphQL();
}