feat: add MachineConfig, MaterialConfig, MachineSummary with parameter lookup

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

OpenNest.Data/MachineConfig.cs

@@ -0,0 +1,26 @@
+using OpenNest.Math;
+
+namespace OpenNest.Data;
+
+public class MachineConfig
+{
+    public Guid Id { get; set; } = Guid.NewGuid();
+    public int SchemaVersion { get; set; } = 1;
+    public string Name { get; set; } = "";
+    public MachineType Type { get; set; } = MachineType.Laser;
+    public UnitSystem Units { get; set; } = UnitSystem.Inches;
+    public List<MaterialConfig> Materials { get; set; } = new();
+
+    public ThicknessConfig? GetParameters(string material, double thickness)
+    {
+        var mat = GetMaterial(material);
+        if (mat is null) return null;
+        return mat.Thicknesses.FirstOrDefault(t => t.Value.IsEqualTo(thickness));
+    }
+
+    public MaterialConfig? GetMaterial(string name)
+    {
+        return Materials.FirstOrDefault(m =>
+            string.Equals(m.Name, name, StringComparison.OrdinalIgnoreCase));
+    }
+}