refactor(PepLib.Core): reorganize files into logical folder structure

Move 38 files from root directory into organized subfolders:
- Enums/ (7 files): StatusType, ApplicationType, DrawingType, etc.
- Geometry/ (5 files): Vector, Box, Size, Spacing, Node
- Models/ (15 files): Nest, Plate, Part, Program, Report, etc.
- Utilities/ (7 files): MathHelper, Tolerance, ZipHelper, etc.
- Extensions/ (2 files): PartListExtensions, PlateListExtensions
- Interfaces/ (1 file): IMovable

Update namespaces to follow folder hierarchy (e.g., PepLib.Models).
Add GlobalUsings.cs for internal backward compatibility.
Update Codes/ and IO/ files with new using statements.
Update PepApi.Core consumers to reference new namespaces.

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

PepLib.Core/Models/NestInfo.cs

@@ -0,0 +1,98 @@
+using PepLib.Enums;
+using PepLib.IO;
+
+namespace PepLib.Models
+{
+    public class NestInfo
+    {
+        public string Name { get; set; }
+
+        public DateTime DateCreated { get; set; }
+
+        public DateTime DateLastModified { get; set; }
+
+        public StatusType Status { get; set; }
+
+        public int LoopCount { get; set; }
+
+        public int ProgramCount { get; set; }
+
+        public int PlateCount { get; set; }
+
+        public string Comments { get; set; }
+
+        public string Customer { get; set; }
+
+        public string ProgrammedBy { get; set; }
+
+        public int MaterialNumber { get; set; }
+
+        public string MaterialGrade { get; set; }
+
+        public string Notes { get; set; }
+
+        public string DefaultPlateSize { get; set; }
+
+        public string Kerf { get; set; }
+
+        public string PostedAs { get; set; }
+
+        public string Errors { get; set; }
+
+        public string UserDefined1 { get; set; }
+
+        public string UserDefined2 { get; set; }
+
+        public string UserDefined3 { get; set; }
+
+        public string UserDefined4 { get; set; }
+
+        public string UserDefined5 { get; set; }
+
+        public string UserDefined6 { get; set; }
+
+        public static NestInfo Load(string nestFile)
+        {
+            var reader = new NestInfoReader();
+            reader.Read(nestFile);
+            return reader.Info;
+        }
+
+        public static NestInfo Load(Stream stream)
+        {
+            var reader = new NestInfoReader();
+            reader.Read(stream);
+            return reader.Info;
+        }
+
+        public static bool TryLoad(string nestFile, out NestInfo nestInfo)
+        {
+            try
+            {
+                nestInfo = Load(nestFile);
+            }
+            catch (Exception)
+            {
+                nestInfo = null;
+                return false;
+            }
+
+            return true;
+        }
+
+        public static bool TryLoad(Stream stream, out NestInfo nestInfo)
+        {
+            try
+            {
+                nestInfo = Load(stream);
+            }
+            catch (Exception)
+            {
+                nestInfo = null;
+                return false;
+            }
+
+            return true;
+        }
+    }
+}