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/Geometry/Box.cs

@@ -0,0 +1,149 @@
+namespace PepLib.Geometry
+{
+    public class Box
+    {
+        public Box()
+            : this(0, 0, 0, 0)
+        {
+        }
+
+        public Box(double x, double y, double w, double h)
+        {
+            Location = new Vector(x, y);
+            Size = new Size(0, 0);
+            Width = w;
+            Height = h;
+        }
+
+        public Vector Location;
+
+        public Vector Center
+        {
+            get { return new Vector(X + Width * 0.5, Y + Height * 0.5); }
+        }
+
+        public Size Size;
+
+        public double X
+        {
+            get { return Location.X; }
+            set { Location.X = value; }
+        }
+
+        public double Y
+        {
+            get { return Location.Y; }
+            set { Location.Y = value; }
+        }
+
+        public double Width
+        {
+            get { return Size.Width; }
+            set { Size.Width = value; }
+        }
+
+        public double Height
+        {
+            get { return Size.Height; }
+            set { Size.Height = value; }
+        }
+
+        public void MoveTo(double x, double y)
+        {
+            X = x;
+            Y = y;
+        }
+
+        public void MoveTo(Vector pt)
+        {
+            X = pt.X;
+            Y = pt.Y;
+        }
+
+        public void Offset(double x, double y)
+        {
+            X += x;
+            Y += y;
+        }
+
+        public void Offset(Vector voffset)
+        {
+            Location += voffset;
+        }
+
+        public double Left
+        {
+            get { return X; }
+        }
+
+        public double Right
+        {
+            get { return X + Width; }
+        }
+
+        public double Top
+        {
+            get { return Y + Height; }
+        }
+
+        public double Bottom
+        {
+            get { return Y; }
+        }
+
+        public double Area()
+        {
+            return Width * Height;
+        }
+
+        public double Perimeter()
+        {
+            return Width * 2 + Height * 2;
+        }
+
+        public bool IsIntersecting(Box box)
+        {
+            if (Left >= box.Right)
+                return false;
+
+            if (Right >= box.Left)
+                return false;
+
+            if (Top <= box.Bottom)
+                return false;
+
+            if (Bottom <= box.Top)
+                return false;
+
+            return true;
+        }
+
+        public bool Contains(Box box)
+        {
+            if (box.Left < Left)
+                return false;
+
+            if (box.Right > Right)
+                return false;
+
+            if (box.Bottom < Bottom)
+                return false;
+
+            if (box.Top > Top)
+                return false;
+
+            return true;
+        }
+
+        public bool Contains(Vector pt)
+        {
+            return pt.X >= Left && pt.X <= Right
+                && pt.Y >= Bottom && pt.Y <= Top;
+        }
+
+        public override string ToString()
+        {
+            return string.Format("[Box: X={0}, Y={1}, Width={2}, Height={3}]", X, Y, Width, Height);
+        }
+    }
+}