fix:修复板擦面积问题

Ink Canvas/MainWindow_cs/MW_FloatingBarIcons.cs

@@ -1502,7 +1502,7 @@ namespace Ink_Canvas {
                     k = Settings.Canvas.EraserShapeType == 0 ? 1.25 : 1.2;
                     break;
                 case 4:
-                    k = Settings.Canvas.EraserShapeType == 0 ? 1.8 : 1.6;
+                    k = Settings.Canvas.EraserShapeType == 0 ? 1.5 : 1.3;
                     break;
             }
 

Ink Canvas/MainWindow_cs/MW_SettingsToLoad.cs

@@ -485,7 +485,7 @@ namespace Ink_Canvas {
                                 k = 1.25;
                                 break;
                             case 4:
-                                k = 1.8;
+                                k = 1.5;
                                 break;
                         }
 
@@ -506,7 +506,7 @@ namespace Ink_Canvas {
                                 k = 1.2;
                                 break;
                             case 4:
-                                k = 1.6;
+                                k = 1.5;
                                 break;
                         }
 

Ink Canvas/MainWindow_cs/MW_ShapeDrawing.cs

@@ -521,7 +521,7 @@ namespace Ink_Canvas {
                             k = 1.25;
                             break;
                         case 4:
-                            k = 1.8;
+                            k = 1.5;
                             break;
                     }
 

Ink Canvas/MainWindow_cs/MW_TouchEvents.cs

@@ -68,7 +68,7 @@ namespace Ink_Canvas {
                         k = 1.25;
                         break;
                     case 4:
-                        k = 1.8;
+                        k = 1.5;
                         break;
                 }
 
@@ -255,7 +255,7 @@ namespace Ink_Canvas {
                             k = 1.25;
                             break;
                         case 4:
-                            k = 1.8;
+                            k = 1.5;
                             break;
                     }