* 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>