Fix the 'Mask' node from always erroring (#2474)

Fix mask node upstream input calculation.

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

Author: singhutsav5502

editor/src/messages/portfolio/document/node_graph/document_node_definitions.rs

@@ -809,6 +809,7 @@ fn static_nodes() -> Vec<DocumentNodeDefinition> {
 						NodeInput::value(TaggedValue::ImageFrame(ImageFrameTable::one_empty_image()), true),
 						NodeInput::value(TaggedValue::ImageFrame(ImageFrameTable::one_empty_image()), true),
 					],
+					manual_composition: Some(generic!(T)),
 					..Default::default()
 				},
 				persistent_node_metadata: DocumentNodePersistentMetadata {