style: apply CSharpier formatting to all C# sources

Repo-wide sweep with the pinned CSharpier 1.3.0 tool. Whitespace and
line-wrapping only; OpenNest.Engine.Tests (109) and OpenNest.IO.Tests
pass after reformat, full solution builds 0 errors.

Added .csharpierignore so csproj/config XML keeps its existing layout
(CSharpier's XML wrapping churns attributes with zero benefit).

Formatting is now enforceable: dotnet csharpier check . passes.

OpenNest.Engine/CirclePacking/Bin.cs

@@ -1,6 +1,6 @@
-using OpenNest.Geometry;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Linq;
+using OpenNest.Geometry;
 
 namespace OpenNest.CirclePacking
 {
@@ -24,7 +24,7 @@ namespace OpenNest.CirclePacking
             {
                 Location = this.Location,
                 Size = this.Size,
-                Items = new List<Item>(Items)
+                Items = new List<Item>(Items),
             };
         }
     }

OpenNest.Engine/CirclePacking/FillEndEven.cs

@@ -1,21 +1,20 @@
-using OpenNest.Geometry;
+using System;
+using OpenNest.Geometry;
 using OpenNest.Math;
-using System;
 
 namespace OpenNest.CirclePacking
 {
     internal class FillEndEven : FillEngine
     {
         public FillEndEven(Bin bin)
-            : base(bin)
-        {
-        }
+            : base(bin) { }
 
         public override void Fill(Item item)
         {
             var max = new Vector(
                 Bin.Right - item.BoundingBox.Right + Tolerance.Epsilon,
-                Bin.Top - item.BoundingBox.Top + Tolerance.Epsilon);
+                Bin.Top - item.BoundingBox.Top + Tolerance.Epsilon
+            );
 
             var rows = System.Math.Floor((Bin.Length + Tolerance.Epsilon) / (item.Diameter));
 
@@ -36,10 +35,7 @@ namespace OpenNest.CirclePacking
 
                     for (; y <= max.Y; y += yoffset)
                     {
-                        Bin.Items.Add(new Item
-                        {
-                            Center = new Vector(x, y)
-                        });
+                        Bin.Items.Add(new Item { Center = new Vector(x, y) });
                     }
 
                     column++;
@@ -62,10 +58,7 @@ namespace OpenNest.CirclePacking
 
                     for (; y <= max.Y; y += yoffset)
                     {
-                        Bin.Items.Add(new Item
-                        {
-                            Center = new Vector(x, y)
-                        });
+                        Bin.Items.Add(new Item { Center = new Vector(x, y) });
                     }
 
                     column++;

OpenNest.Engine/CirclePacking/FillEndOdd.cs

@@ -1,15 +1,13 @@
-using OpenNest.Geometry;
+using System;
+using OpenNest.Geometry;
 using OpenNest.Math;
-using System;
 
 namespace OpenNest.CirclePacking
 {
     internal class FillEndOdd : FillEngine
     {
         public FillEndOdd(Bin bin)
-            : base(bin)
-        {
-        }
+            : base(bin) { }
 
         public override void Fill(Item item)
         {
@@ -37,7 +35,8 @@ namespace OpenNest.CirclePacking
 
             var max = new Vector(
                 bin.Right - item.BoundingBox.Right + Tolerance.Epsilon,
-                bin.Top - item.BoundingBox.Top + Tolerance.Epsilon);
+                bin.Top - item.BoundingBox.Top + Tolerance.Epsilon
+            );
 
             var primarySize = horizontal ? bin.Width : bin.Length;
             var count = System.Math.Floor((primarySize + Tolerance.Epsilon) / item.Diameter);
@@ -64,7 +63,9 @@ namespace OpenNest.CirclePacking
                 for (; inner <= innerMax; inner += primaryOffset)
                 {
                     var addedItem = item.Clone() as Item;
-                    addedItem.Center = horizontal ? new Vector(inner, outer) : new Vector(outer, inner);
+                    addedItem.Center = horizontal
+                        ? new Vector(inner, outer)
+                        : new Vector(outer, inner);
                     bin.Items.Add(addedItem);
                 }
 

OpenNest.Engine/CirclePacking/FillEngine.cs

@@ -1,5 +1,4 @@
-
-namespace OpenNest.CirclePacking
+namespace OpenNest.CirclePacking
 {
     internal abstract class FillEngine
     {

OpenNest.Engine/CirclePacking/Item.cs

@@ -12,7 +12,7 @@ namespace OpenNest.CirclePacking
             {
                 Radius = this.Radius,
                 Center = this.Center,
-                Id = this.Id
+                Id = this.Id,
             };
         }
     }