Refactor the TypeScript data flow for full type safety and auto-generation of Rust types (#3865)

* Migrate Specta to Tsify to auto-generate messages.ts, working except colors and widgets

* Adopt the generated FillColor/Color/GradientStops

* Fix widget typing

* Separate WidgetGroup enum variants into wrapper structs

* Small rename

* Simplify widgets further

* Clean up message type references

* Switch type imports to the auto-generated file

* Remove lowercase serde rename

* Fix FillChoice deserialization

* Fix small regression from #3837

* Improve type safety

* Make WidgetSpan type-safe

* More cleanup and type safety

* More type safety

* More type safety

* Get the rest to type-check without errors; improve widget builder macro to have optional icons; improve Svelte 5 configs

* Cargo fmt

* Fix imports

* Update outdated readme info

* Fix lint command rename references

* Fix typos

* One more typos fix

* Remove unnecessary dep: prefix from the edited Cargo.toml files

* Remove excess parts from Cargo.toml

* Fix compiling on desktop

* Revert "Remove excess parts from Cargo.toml"

This reverts commit 6b711117b3a5d5d8a3ee20f36a43bc74930b7c82.

* Update dev docs with simpler, more accurate instructions

editor/src/messages/preferences/preferences_message_handler.rs

@@ -11,7 +11,8 @@ pub struct PreferencesMessageContext<'a> {
 	pub tool_message_handler: &'a ToolMessageHandler,
 }
 
-#[derive(Debug, PartialEq, Clone, serde::Serialize, serde::Deserialize, specta::Type, ExtractField)]
+#[cfg_attr(feature = "wasm", derive(tsify::Tsify))]
+#[derive(Debug, PartialEq, Clone, serde::Serialize, serde::Deserialize, ExtractField)]
 #[serde(default)]
 pub struct PreferencesMessageHandler {
 	pub selection_mode: SelectionMode,

editor/src/messages/preferences/utility_types.rs

@@ -1,4 +1,5 @@
-#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, serde::Serialize, serde::Deserialize, specta::Type, Hash)]
+#[cfg_attr(feature = "wasm", derive(tsify::Tsify))]
+#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, serde::Serialize, serde::Deserialize, Hash)]
 pub enum SelectionMode {
 	#[default]
 	Touched = 0,