Rename SawCut library to CutList.Core

Rename the core library project from SawCut to CutList.Core for consistent
branding across the solution. This includes:
- Rename project folder and .csproj file
- Update namespace from SawCut to CutList.Core
- Update all using statements and project references

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CutList.Core/ArchUnits.cs

@@ -0,0 +1,75 @@
+using System;
+using System.Text;
+using System.Text.RegularExpressions;
+
+namespace CutList.Core
+{
+    public static class ArchUnits
+    {
+        public static double ParseToInches(string input)
+        {
+            if (string.IsNullOrWhiteSpace(input))
+                return 0;
+
+            var sb = new StringBuilder(input.Trim().ToLower());
+
+            // replace all units with their equivelant symbols
+            sb.Replace("ft", "'");
+            sb.Replace("feet", "'");
+            sb.Replace("foot", "'");
+            sb.Replace("inches", "\"");
+            sb.Replace("inch", "\"");
+            sb.Replace("in", "\"");
+
+            var regex = new Regex("^(?<Feet>\\d+\\.?\\d*\\s*')?\\s*(?<Inches>\\d+\\.?\\d*\\s*\")?$");
+
+            // input manipulation is done, put the value back
+            input = Fraction.ReplaceFractionsWithDecimals(sb.ToString());
+
+            var match2 = regex.Match(input);
+
+            if (!match2.Success)
+                throw new Exception("Input is not in a valid format.");
+
+            var feet = match2.Groups["Feet"];
+            var inches = match2.Groups["Inches"];
+
+            var totalInches = 0.0;
+
+            if (feet.Success)
+            {
+                var x = double.Parse(feet.Value.Remove(feet.Length - 1));
+                totalInches += x * 12;
+            }
+
+            if (inches.Success)
+            {
+                var x = double.Parse(inches.Value.Remove(inches.Length - 1));
+                totalInches += x;
+            }
+
+            return Math.Round(totalInches, 8);
+        }
+
+        public static double ParseToFeet(string input)
+        {
+            var inches = ParseToInches(input);
+            return Math.Round(inches / 12.0, 8);
+        }
+
+        public static string FormatFromInches(double totalInches)
+        {
+            var feet = Math.Floor(totalInches / 12.0);
+            var inches = FormatHelper.ConvertToMixedFraction(totalInches - (feet * 12.0));
+
+            if (feet > 0)
+            {
+                return $"{feet}'  {inches}\"";
+            }
+            else
+            {
+                return $"{inches}\"";
+            }
+        }
+    }
+}