SPMD SIMD math library & lock-free job system integration

- Add new SPMD SIMD math project with scalar/vector lanes
- Integrate SPMD jobs and scheduling into job system
- Implement lock-free job dependency management
- Update math functions for .NET 10 and SIMD performance
- Add SPMD benchmarks, compress-store tests, and race tests
- Introduce generic Result<T> error handling utilities
- Solution/project file updates and code cleanup

Misaki.HighPerformance.Jobs/JobHandle.cs

@@ -1,18 +1,21 @@
-namespace Misaki.HighPerformance.Jobs;
+namespace Misaki.HighPerformance.Jobs;
 
 public readonly struct JobHandle : IEquatable<JobHandle>
 {
-    internal readonly int _id;
-    internal readonly int _generation;
+    private readonly int _id;
+    private readonly int _generation;
 
-    public static JobHandle Invalid => new(-1, -1);
+    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;
-        _generation = generation;
+        _id = id + 1;
+        _generation = generation + 1;
     }
 
     public bool Equals(JobHandle other)