Fix an assortment of small bugs (#3968)

* Fix an assertion failure bug when scaling a line in the transform cage

* Fix missing defaults on node gradient inputs

* Fix Blend Shapes path input wire not updating to show in the UI after Layer > Blend

* Fix assertion failure due to browser non-monotonic timestamp

* Fix SVG renderer drawing 1px strokes as half-width when using stroke alignment

* Fix incorrect appearance of the ColorInput widget when set to "none" and "disabled"

* Fix lerp function in Fill enum to handle None cases correctly

* Fix stroke alignment bug

editor/src/messages/input_mapper/utility_types/misc.rs

@@ -139,7 +139,8 @@ impl FrameTimeInfo {
 	}
 
 	pub fn advance_timestamp(&mut self, next_timestamp: Duration) {
-		debug_assert!(next_timestamp >= self.timestamp);
+		// Guard against non-monotonic timestamps from the browser (Keavon observed this once in Chrome)
+		let next_timestamp = next_timestamp.max(self.timestamp);
 
 		self.prev_timestamp = Some(self.timestamp);
 		self.timestamp = next_timestamp;

editor/src/messages/portfolio/document/utility_types/network_interface.rs

@@ -4005,6 +4005,14 @@ impl NodeNetworkInterface {
 				}
 			}
 			(_, NodeInput::Node { node_id: upstream_node_id, .. }) => {
+				// If the old input wasn't exposed but the new one is (`Node` inputs are always exposed),
+				// the node's port count changed, so its click targets need to be recomputed
+				if !old_input.is_exposed()
+					&& let InputConnector::Node { node_id, .. } = input_connector
+				{
+					self.unload_node_click_targets(node_id, network_path);
+				}
+
 				// Load structure if the change is to the document network and to the first or second
 				if network_path.is_empty() {
 					if matches!(input_connector, InputConnector::Export(0)) {

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

@@ -212,16 +212,15 @@ impl SelectedEdges {
 				let original_from_pivot = updated - pivot; // The original vector from the point to the pivot
 				let mut scale_factor = new_from_pivot / original_from_pivot;
 
-				// Constrain should always scale by the same factor in x and y
+				// Constrain should always scale by the same factor in x and y.
+				// When one axis of `original_from_pivot` is near zero (e.g. for a line's degenerate bounding box),
+				// the scale factor for that axis is numerically unstable, so we copy from the more stable axis.
 				if constrain {
-					// When the point is on the pivot, we simply copy the other axis.
-					if original_from_pivot.x.abs() < 1e-5 {
+					if original_from_pivot.x.abs() < original_from_pivot.y.abs() {
 						scale_factor.x = scale_factor.y;
-					} else if original_from_pivot.y.abs() < 1e-5 {
+					} else {
 						scale_factor.y = scale_factor.x;
 					}
-
-					debug_assert!((scale_factor.x - scale_factor.y).abs() < 1e-5);
 				}
 
 				if !(self.left || self.right || constrain) {