feat: add auto-tab size range fields to CuttingParameters

Add AutoTabMinSize and AutoTabMaxSize properties to enable automatic tab
assignment based on part size. Update CuttingParametersSerializer for
round-trip serialization and add tests.

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

OpenNest.Core/CNC/CuttingStrategy/CuttingParameters.cs

@@ -23,6 +23,9 @@ namespace OpenNest.CNC.CuttingStrategy
 
         public double PierceClearance { get; set; } = 0.0625;
 
+        public double AutoTabMinSize { get; set; }
+        public double AutoTabMaxSize { get; set; }
+
         public Tab TabConfig { get; set; }
         public bool TabsEnabled { get; set; }