Integrate the node graph as a Node Graph Frame layer type (#812)

* Add node graph frame tool

* Add a brighten

* Use the node graph

* Fix topological_sort

* Update UI

* Add icons for the tool and layer type

* Avoid serde & use bitmaps to improve performance

* Allow serialising a node graph

* Fix missing ..Default::default()

* Fix incorrect comments

* Cache node graph output image

* Suppress no-cycle import warning

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

editor/src/messages/tool/tool_message.rs

@@ -78,6 +78,9 @@ pub enum ToolMessage {
 	#[remain::unsorted]
 	#[child]
 	Imaginate(ImaginateToolMessage),
+	#[remain::unsorted]
+	#[child]
+	NodeGraphFrame(NodeGraphFrameToolMessage),
 
 	// Messages
 	#[remain::unsorted]
@@ -114,6 +117,8 @@ pub enum ToolMessage {
 
 	#[remain::unsorted]
 	ActivateToolImaginate,
+	#[remain::unsorted]
+	ActivateToolNodeGraphFrame,
 
 	ActivateTool {
 		tool_type: ToolType,