feat: add Configuration class with user-tunable defaults

Core/Configuration.cs

@@ -0,0 +1,21 @@
+namespace VoxelEngine.Core;
+
+public sealed class Configuration
+{
+    public int RenderDistanceHorizontal { get; set; } = 8;
+    public int RenderDistanceVertical { get; set; } = 4;
+    public int SpawnReadyRadiusHorizontal { get; set; } = 1;
+
+    public int MaxGenerateJobsInFlight { get; set; } = 8;
+    public int MaxMeshUploadsPerFrame { get; set; } = 4;
+    public int WorkerThreadCount { get; set; } = Math.Max(1, Environment.ProcessorCount - 1);
+
+    public float MoveSpeed { get; set; } = 8f;
+    public float MouseSensitivity { get; set; } = 0.15f;
+    public float Fov { get; set; } = 60f;
+
+    public int WindowWidth { get; set; } = 1280;
+    public int WindowHeight { get; set; } = 720;
+
+    public int? Seed { get; set; } = null;
+}