feat(jobs): optimize job data copy and add default opts

Replaces Unsafe.Copy/NativeMemory.Copy with direct pointer assignment for job data in JobScheduler, improving performance and code clarity. Adds a static Default property to AllocationManagerInitOpts for easier initialization. Updates test setup to use the new default options. Bumps assembly version to 1.5.7.

Misaki.HighPerformance.Test/UnitTest/Jobs/TestJobSystem.cs

@@ -22,6 +22,7 @@ public unsafe class TestJobSystem
     [ClassInitialize]
     public static void Initialize(TestContext testContext)
     {
+        AllocationManager.Initialize(AllocationManagerInitOpts.Default);
         s_jobScheduler = new JobScheduler(3);
     }