Reply rendering (#861)

* Cleanup how we use message timeline items in preparation for rich reply rendering

* Expose reply details up to the UI level

* Render replies in the timeline (textual for now). Remove now unused AttributedStringBuilderComponent isReply flag.

* Move reply detail loading to when the item appears instead of when it's created.

* Fix unit tests

* Fetch event details also when the reply details are in the error state

* Tweaks following code review

* Localise emote bodies

* Fix replies not loading sometimes, use the current event identifier instead of the one being replied to

ElementX/Sources/Services/Timeline/TimelineItems/EventBasedMessageTimelineItemProtocol.swift

@@ -0,0 +1,22 @@
+//
+// Copyright 2023 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 Foundation
+
+protocol EventBasedMessageTimelineItemProtocol: EventBasedTimelineItemProtocol {
+    var body: String { get }
+    var replyDetails: TimelineItemReplyDetails? { get }
+}