Fix transforms, Brush tool, and G/R/S (#1473)

* Transform fixes

* Fix the desert artwork

* Change artboard icon

* Better handling when transforming brush strokes

* Code review pass

---------

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

node-graph/gcore/src/raster/image.rs

@@ -349,6 +349,13 @@ impl<P: Hash + Pixel> Hash for ImageFrame<P> {
 	}
 }
 
+impl<P: Pixel> ImageFrame<P> {
+	/// Compute the pivot in local space with the current transform applied
+	pub fn local_pivot(&self, normalized_pivot: DVec2) -> DVec2 {
+		self.transform.transform_point2(normalized_pivot)
+	}
+}
+
 /* This does not work because of missing specialization
  * so we have to manually implement this for now
 impl<S: Into<P> + Pixel, P: Pixel> From<Image<S>> for Image<P> {