Groundwork for integrating Specta (#949)

* add derive(specta::Type)

* use specta from git

* introduce Uuid type

* remove unnecessary specta::Type

* document export_types test

* upgrade Specta
The previous Specta branch had some hacks that were just for this project. They have all been converted into proper features so they can be merged into main.

* remove some unnecessary specta::Type uses

* add MessageDiscriminantDef explanation

* manually export types with specta

* rename 'specta.rs' to 'export_types.rs'

* rename 'export_types' to 'generate_ts_types'

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Co-authored-by: Oscar Beaumont <oscar@otbeaumont.me>

editor/src/messages/portfolio/document/artboard/artboard_message_handler.rs

@@ -12,7 +12,7 @@ use document_legacy::Operation as DocumentOperation;
 use glam::DAffine2;
 use serde::{Deserialize, Serialize};
 
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq)]
+#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, specta::Type)]
 pub struct ArtboardMessageHandler {
 	pub artboards_document: DocumentLegacy,
 	pub artboard_ids: Vec<LayerId>,