Refactor IndexedDB document persistence to reuse data structures of desktop persistence (#4020)

* Switch indexedDb document serialized struct from camelCase to snake_case

* Refactor and migrate old indexedDb format to the same shape as desktop persistence

* Avoid duplicate struct definitions in the desktop crate

* Refactor frontend message handling to consolidate auto-save document loading

* Code review

* Review

---------

Co-authored-by: Timon <me@timon.zip>

desktop/wrapper/src/messages.rs

@@ -3,6 +3,7 @@ use std::path::PathBuf;
 
 pub(crate) use graphite_editor::messages::prelude::Message as EditorMessage;
 
+pub use graphite_editor::messages::frontend::utility_types::{PersistedDocumentInfo, PersistedState};
 pub use graphite_editor::messages::input_mapper::utility_types::input_keyboard::{Key, ModifierKeys};
 pub use graphite_editor::messages::input_mapper::utility_types::input_mouse::{EditorMouseState as MouseState, EditorPosition as Position, MouseKeys};
 pub use graphite_editor::messages::prelude::DocumentId;
@@ -49,8 +50,7 @@ pub enum DesktopFrontendMessage {
 	PersistenceUpdateCurrentDocument {
 		id: DocumentId,
 	},
-	PersistenceLoadCurrentDocument,
-	PersistenceLoadRemainingDocuments,
+	PersistenceLoadDocuments,
 	PersistenceUpdateDocumentsList {
 		ids: Vec<DocumentId>,
 	},