feat: 新增环形自由锻中心冲孔CAD绘图器。

Cad/Drawers/RingRawFreeForgeCenterPunchDrawer.cs

@@ -145,11 +145,25 @@ namespace CadParamPluging.Cad.Drawers
                  // Right Side of Left Section is Inner -> innerFilletR
                  DrawSectionWithAsymmetricFillets(ctx, ox, xInnerLeftVal, oy, H, outerFilletR, innerFilletR);
 
+                 if (innerFilletR > 0)
+                 {
+                     double cxLeft = xInnerLeftVal - innerFilletR;
+                     double cyLeft = oy + H - innerFilletR;
+                     DrawInnerRadiusLeader(ctx, cxLeft, cyLeft, innerFilletR, true);
+                 }
+
                  // Draw Right Section Contour (Inner Edge: xInnerRightVal, Outer Edge: ox + W)
                  // Left Side of Right Section is Inner -> innerFilletR
                  // Right Side of Right Section is Outer -> outerFilletR
                  DrawSectionWithAsymmetricFillets(ctx, xInnerRightVal, ox + W, oy, H, innerFilletR, outerFilletR);
 
+                 if (innerFilletR > 0)
+                 {
+                     double cxRight = xInnerRightVal + innerFilletR;
+                     double cyRight = oy + H - innerFilletR;
+                     DrawInnerRadiusLeader(ctx, cxRight, cyRight, innerFilletR, false);
+                 }
+
                  // Draw Connecting Lines (Hole Back View) - Top and Bottom
                  // Extend into the inner fillet radius
                  
@@ -357,6 +371,77 @@ namespace CadParamPluging.Cad.Drawers
             CreateHatchForPolyline(ctx, poly);
         }
 
+        private static void DrawInnerRadiusLeader(FeatureDrivenDrawer.DrawingContext ctx, double cx, double cy, double r, bool isLeftSection)
+        {
+            try
+            {
+                var val = ctx.OriginalBag?.GetDoubleOrNull(FeatureDrivenDrawer.KeyInnerRadiusMax);
+                if (!val.HasValue || val.Value <= 0) return;
+
+                double angleDeg = isLeftSection ? 45 : 135;
+                double angleRad = angleDeg * Math.PI / 180.0;
+                
+                // 起点（指向圆弧：圆心延角度方向在圆弧上的点）
+                double px = cx + r * Math.Cos(angleRad);
+                double py = cy + r * Math.Sin(angleRad);
+
+                // 终点（沿着同一角度延伸出去一定长度作为引出线，比如长 25）
+                double ex = px + 25 * Math.Cos(angleRad);
+                double ey = py + 25 * Math.Sin(angleRad);
+
+                var leader = new Leader();
+                leader.SetDatabaseDefaults();
+                leader.AppendVertex(new Point3d(px, py, 0));
+                leader.AppendVertex(new Point3d(ex, ey, 0));
+                leader.HasArrowHead = true;
+                ctx.Style?.Apply(leader, DrawingStyleManager.Role.Dimension);
+                leader.ColorIndex = 4; // Cyan
+
+                ctx.Btr.AppendEntity(leader);
+                ctx.Tr.AddNewlyCreatedDBObject(leader, true);
+
+                // 文字（与线对齐同角度）
+                var textStr = $"R\\U+2264{val.Value}";
+                var text = new DBText();
+                text.TextString = textStr;
+                text.Height = 3.5;
+                text.ColorIndex = 4;
+                
+                // 倾斜文字角度
+                double textRotation = angleRad;
+                if (!isLeftSection)
+                {
+                    // For the right side (135 degrees), we want the text to read left-to-right
+                    // So we subtract 180 degrees (PI) from the angle, which makes it -45 degrees
+                    textRotation = angleRad - Math.PI; 
+                }
+                text.Rotation = textRotation; 
+                
+                // 对齐设置
+                text.HorizontalMode = TextHorizontalMode.TextCenter;
+                text.VerticalMode = TextVerticalMode.TextBottom;
+                
+                // 计算文字放置点，紧贴在结束点上方
+                // 为了让文字准确地骑在线上，基于文字的旋转角度计算偏移
+                double offsetX = 2.0 * Math.Cos(textRotation + Math.PI / 2);
+                double offsetY = 2.0 * Math.Sin(textRotation + Math.PI / 2);
+                
+                var tp = new Point3d(ex + offsetX, ey + offsetY, 0);
+                text.AlignmentPoint = tp;
+                text.Position = tp;
+
+                ctx.Style?.Apply(text, DrawingStyleManager.Role.Text);
+                text.ColorIndex = 4;
+
+                ctx.Btr.AppendEntity(text);
+                ctx.Tr.AddNewlyCreatedDBObject(text, true);
+            }
+            catch
+            {
+                // ignore
+            }
+        }
+
         private static void CreateHatchForPolyline(FeatureDrivenDrawer.DrawingContext ctx, Polyline boundary)
         {
             try