Refactor how drafts are handled on a coordinator level and add support for them on thread timelines.

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/ComposerToolbarModels.swift

@@ -39,6 +39,8 @@ enum ComposerToolbarViewModelAction {
 
 enum ComposerToolbarViewAction {
     case composerAppeared
+    case composerDisappeared
+    
     case sendMessage
     case editLastMessage
     case cancelReply

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/ComposerToolbarViewModel.swift

@@ -161,9 +161,22 @@ final class ComposerToolbarViewModel: ComposerToolbarViewModelType, ComposerTool
             }
         }
         .store(in: &cancellables)
+        
+        NotificationCenter.default.publisher(for: UIApplication.willResignActiveNotification).sink { [weak self] _ in
+            self?.saveDraft()
+        }
+        .store(in: &cancellables)
     }
     
     // MARK: - Public
+    
+    func start() {
+        Task { await loadDraft() }
+    }
+    
+    func stop() {
+        saveDraft()
+    }
 
     override func process(viewAction: ComposerToolbarViewAction) {
         switch viewAction {
@@ -172,6 +185,8 @@ final class ComposerToolbarViewModel: ComposerToolbarViewModelType, ComposerTool
                 hasAppeard = true
                 wysiwygViewModel.setup()
             }
+        case .composerDisappeared:
+            saveDraft()
         case .sendMessage:
             guard !state.sendButtonDisabled else { return }
             

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/ComposerToolbarViewModelProtocol.swift

@@ -13,8 +13,9 @@ import WysiwygComposer
 protocol ComposerToolbarViewModelProtocol {
     var actions: AnyPublisher<ComposerToolbarViewModelAction, Never> { get }
     var context: ComposerToolbarViewModelType.Context { get }
+    
+    func start()
+    func stop()
 
     func process(timelineAction: TimelineComposerAction)
-    func loadDraft() async
-    func saveDraft()
 }

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/View/ComposerToolbar.swift

@@ -181,6 +181,9 @@ struct ComposerToolbar: View {
         } onAppearAction: {
             context.send(viewAction: .composerAppeared)
         }
+        .onDisappear {
+            context.send(viewAction: .composerDisappeared)
+        }
         .environmentObject(context)
         .focused($composerFocused)
         .padding(.leading, context.composerFormattingEnabled ? 7 : 0)