Add inpainting and outpainting to Imaginate (#864)

* Do not select layer immediatly on drag

* Add LayerReferenceInput MVP widget

* Properties Panel

* Fix dragging marker flicker

* Change mask shape to outline

* Add mask rendering

* Simplify select code

* Remove colours

* Fix inpaint/outpaint and rearrage widget UX

* Add mask blur and mask starting fill parameters

* Guard for the case when the layer is missing

* Add icon to LayerReferenceInput to finalize its UI

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

frontend/wasm/src/editor_api.rs

@@ -179,7 +179,7 @@ impl JsEditorHandle {
 				self.dispatch(message);
 				Ok(())
 			}
-			_ => Err(Error::new("Could not update UI").into()),
+			(target, val) => Err(Error::new(&format!("Could not update UI\nDetails:\nTarget: {:?}\nValue: {:?}", target, val)).into()),
 		}
 	}