Fix regression causing pasted images to have a zero-size transform (#2238)

* Use the identity matrix as the default for an image frame

* Fix all usages to be equivalent to their pre-refactor versions, opting to keep ZERO not IDENTITY as the default image size

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

node-graph/gstd/src/brush.rs

@@ -272,7 +272,7 @@ fn brush(_: Footprint, image: ImageFrameTable<Color>, bounds: ImageFrameTable<Co
 		let opaque_image = ImageFrame {
 			image: Image::new(bbox.size().x as u32, bbox.size().y as u32, Color::WHITE),
 			transform: background_bounds,
-			..Default::default()
+			alpha_blending: Default::default(),
 		};
 		let mut erase_restore_mask = opaque_image;