RoomScreenViewModel is now TimelineViewModel (#3157)

Co-authored-by: Stefan Ceriu <stefanc@matrix.org>

ElementX/Sources/Screens/Timeline/TimelineViewModelProtocol.swift

@@ -0,0 +1,29 @@
+//
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Combine
+import Foundation
+import SwiftUI
+
+@MainActor
+protocol TimelineViewModelProtocol {
+    var actions: AnyPublisher<TimelineViewModelAction, Never> { get }
+    var context: TimelineViewModel.Context { get }
+    func process(composerAction: ComposerToolbarViewModelAction)
+    /// Updates the timeline to show and highlight the item with the corresponding event ID.
+    func focusOnEvent(eventID: String) async
+    func stop()
+}