Fix glitches when loading the timeline: use locally generated stable identifiers for all possible timeline items

ElementX/Sources/Services/Timeline/TimelineItems/Items/Virtual/PaginationIndicatorRoomTimelineItem.swift

@@ -17,5 +17,5 @@
 import Foundation
 
 struct PaginationIndicatorRoomTimelineItem: DecorationTimelineItemProtocol, Identifiable, Hashable {
-    let id: String = UUID().uuidString
+    let id = "paginationIndicatorTimelineItemIdentifier"
 }

ElementX/Sources/Services/Timeline/TimelineItems/Items/Virtual/ReadMarkerRoomTimelineItem.swift

@@ -17,5 +17,5 @@
 import Foundation
 
 struct ReadMarkerRoomTimelineItem: DecorationTimelineItemProtocol, Identifiable, Hashable {
-    let id: String = UUID().uuidString
+    let id = "readMarkerTimelineItemIdentifier"
 }

ElementX/Sources/Services/Timeline/TimelineItems/Items/Virtual/SeparatorRoomTimelineItem.swift

@@ -17,6 +17,7 @@
 import Foundation
 
 struct SeparatorRoomTimelineItem: DecorationTimelineItemProtocol, Identifiable, Hashable {
+    #warning("This should really be a stable identifier, ideally coming from the SDK, but unfortunately we receive duplicates for it at the moment, crashing our timeline data source")
     let id: String = UUID().uuidString
     let text: String
 }

ElementX/Sources/Services/Timeline/TimelineItems/Items/Virtual/TimelineStartRoomTimelineItem.swift

@@ -17,6 +17,6 @@
 import Foundation
 
 struct TimelineStartRoomTimelineItem: DecorationTimelineItemProtocol, Identifiable, Hashable {
-    let id: String = UUID().uuidString
+    let id = "timelineStartTimelineItemIdentifier"
     let name: String?
 }