Feat/sync streams

[Chriztiaan]

No description provided.

[simolus3]

Thanks for taking a look at sync streams 🚀 I have a few high-level / API design comments from a quick look, but please treat them as optional since I'm not that familiar with the dotnet SDK.

[simolus3]

I'm not too familiar with dotnet, but generally I prefer to use the canonical duration type of the language (e.g. we're using a Duration for this in Dart). Does TimeSpan work?

[simolus3]

We might introduce more priorities in the future, so exposing this as an enum would be breaking then. See e.g. the Dart type we use for this.

LLM translation that looks reasonable to me:

public readonly record struct StreamPriority : IComparable<StreamPriority>
{
    private const int Highest = 0;

    public int PriorityNumber { get; }

    public StreamPriority(int priorityNumber)
    {
        if (priorityNumber < Highest)
            throw new ArgumentOutOfRangeException(
                nameof(priorityNumber),
                "Priority must be >= 0");

        PriorityNumber = priorityNumber;
    }

    // Higher priority = larger number
    public int CompareTo(StreamPriority other) =>
        other.PriorityNumber.CompareTo(PriorityNumber);

    /// <summary>
    /// The priority used by PowerSync to indicate that a full sync was completed.
    /// </summary>
    public static readonly StreamPriority FullSyncPriority =
        new(int.MaxValue);
}

[simolus3]

It would be nice to either cache this serialization result on the sync description or to perhaps implement an equals check for maps (I don't know if C# has something similar to package:collection's MapEquality).