Update Package structure

Misaki.HighPerformance.Jobs/JobHandle.cs

@@ -0,0 +1,50 @@
+namespace Misaki.HighPerformance.Jobs;
+
+public readonly struct JobHandle : IEquatable<JobHandle>
+{
+    private readonly int _id;
+    private readonly int _generation;
+
+    public int ID => _id - 1;
+    public int Generation => _generation - 1;
+
+    public static JobHandle Invalid => default;
+
+    public bool IsValid => this != Invalid;
+
+    internal JobHandle(int id, int generation)
+    {
+        _id = id + 1;
+        _generation = generation + 1;
+    }
+
+    public bool Equals(JobHandle other)
+    {
+        return _id == other._id && _generation == other._generation;
+    }
+
+    public override bool Equals(object? obj)
+    {
+        return obj is JobHandle handle && Equals(handle);
+    }
+
+    public override int GetHashCode()
+    {
+        return HashCode.Combine(_id, _generation);
+    }
+
+    public override string ToString()
+    {
+        return IsValid ? $"JobHandle({_id}, {_generation})" : "JobHandle(Invalid)";
+    }
+
+    public static bool operator ==(JobHandle left, JobHandle right)
+    {
+        return left.Equals(right);
+    }
+
+    public static bool operator !=(JobHandle left, JobHandle right)
+    {
+        return !(left == right);
+    }
+}