Add Path tool feature for angle locking upon pressing Ctrl while dragging handle over anchor (#2612)

* almost_fixed

* fix need to refactor

* fixed issed need to refactor

* refactor-done fixed issue

* move function to common_functionality

---------

Co-authored-by: Keavon Chambers <keavon@keavon.com>

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

@@ -561,6 +561,13 @@ impl ManipulatorPointId {
 			_ => None,
 		}
 	}
+
+	pub fn get_segment(self) -> Option<SegmentId> {
+		match self {
+			ManipulatorPointId::PrimaryHandle(segment) | ManipulatorPointId::EndHandle(segment) => Some(segment),
+			_ => None,
+		}
+	}
 }
 
 /// The type of handle found on a bézier curve.