* Breadcrumb visualization, nested network consistency, create definitions for Merge internal nodes
* Add index to network inputs, remove imports usage from flatten network
* Replace NodeOutput with NodeInput::Node
* Fully remove imports field, remove unnecessary identity nodes, move Output node to encapsulating network
* Replace previous_outputs with root_node, fix adding artboard/layer to empty network
* Import/Export UI nodes
* Display input/output types dynamically from compiled network
* Add LayerNodeIdentifer::ROOT_PARENT
* Prevent .to_node() on ROOT_PARENT
* Separate NodeGraphMessage and GraphOperationMessage
* General bug fixes with nested networks
* Change layer color, various bug fixes and improvements
* Fix disconnect and set node input for proto nodes and UI export node
* Dashed line to export for previewed node
* Fix deleting proto nodes and nodes that feed into export
* Allow modifications to nodes outside of nested network
* Get network from Node Id parameter
* Change root_node to previous_root_node
* Get TaggedValue from proto node implementation type when disconnecting
* Improve preview functionality and state
* Artboard position and delete children fix
* Name inputs/outputs based on DocumentNodeDefinition or type, fix new artboard/layer insertion
* replace "Link" with "Wire", adjust previewing
* Various bug fixes and improvements
* Modify Sample and Poisson-Disk points, fix incorrect input index and deleting currently viewed node
* Open demo artwork
* Fix opening already upgraded documents and refactor FrontendGraphDataType usages
* Fix deleting within network and other bugs
* Get default node input from compiled network when copying, fix previews, tests, demo artwork
* Code cleanup
* Hide EditorApi and add a comment describing unresolved Import node input types
* Code review
* Replace placeholder ROOT_PARENT NodeId with std::u64::MAX
* Breadcrumb padding
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Co-authored-by: Keavon Chambers <keavon@keavon.com>
