Fix off by one subpath and unrelated crash (#1754)

* Fix off by one in subpath code

* Fix crash with selected handles and anchor

* Sort the correct way I have no idea why the origional code was so overly verbose but it has caused significant confusion and wasted effort

editor/src/messages/tool/common_functionality/shape_editor.rs

@@ -982,10 +982,10 @@ impl ShapeState {
 					continue;
 				}
 
-				selected_points.sort_by(|&a, &b| match a > b {
-					true => std::cmp::Ordering::Greater,
-					false => std::cmp::Ordering::Less,
-				});
+				selected_points.sort();
+
+				// Required to remove duplicates when the handles and anchors are selected
+				selected_points.dedup();
 
 				let mut last_manipulator_index = 0;
 				let mut to_extend_with_last_group: Option<Vec<ManipulatorGroup<ManipulatorGroupId>>> = None;

node-graph/gcore/src/vector/vector_data/attributes.rs

@@ -324,9 +324,9 @@ impl<'a> Iterator for StrokePathIter<'a> {
 			.take_while(|&(_, start, end)| {
 				let continuous = old_end.is_none() || old_end.is_some_and(|old_end| old_end == start);
 				old_end = Some(end);
-				count += 1;
 				continuous
-			});
+			})
+			.inspect(|_| count += 1);
 
 		let subpath = self.vector_data.subpath_from_segments(segments_iter);
 		self.segment_index += count;