Non-decryptable timeline items and debug menu (#300)

* Fixes #292 - Added a timeline item context menu option for printing and showing their debug description
* Fixes #291 - Add support for non-decryptable timeline items

ElementX/Sources/Services/Timeline/TimelineItemProxy.swift

@@ -20,7 +20,7 @@ import MatrixRustSDK
 enum TimelineItemProxy {
     case event(EventTimelineItemProxy)
     case virtual(MatrixRustSDK.VirtualTimelineItem)
-    case other(MatrixRustSDK.TimelineItem)
+    case unknown(MatrixRustSDK.TimelineItem)
     
     init(item: MatrixRustSDK.TimelineItem) {
         if let eventItem = item.asEvent() {
@@ -28,7 +28,7 @@ enum TimelineItemProxy {
         } else if let virtualItem = item.asVirtual() {
             self = .virtual(virtualItem)
         } else {
-            self = .other(item)
+            self = .unknown(item)
         }
     }
 
@@ -42,7 +42,7 @@ enum TimelineItemProxy {
 }
 
 /// A light wrapper around event timeline items returned from Rust.
-struct EventTimelineItemProxy {
+struct EventTimelineItemProxy: CustomDebugStringConvertible {
     let item: MatrixRustSDK.EventTimelineItem
     
     init(item: MatrixRustSDK.EventTimelineItem) {
@@ -94,4 +94,10 @@ struct EventTimelineItemProxy {
             return .now
         }
     }
+    
+    // MARK: - CustomDebugStringConvertible
+    
+    var debugDescription: String {
+        item.fmtDebug()
+    }
 }