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/frontend/frontend_message.rs

@@ -17,7 +17,7 @@ use serde::{Deserialize, Serialize};
 
 #[remain::sorted]
 #[impl_message(Message, Frontend)]
-#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+#[derive(PartialEq, Clone, Debug, Serialize, Deserialize, specta::Type)]
 pub enum FrontendMessage {
 	// Display prefix: make the frontend show something, like a dialog
 	DisplayDialog {