Add support for copying a caption. (#3563)

* Add timeline item action for copying a media caption.

* Fix the action colours when long pressing a timeline item.

Nice side effect: Reasonable sized buttons when button shapes are enabled.

* Re-arrange the Timeline Item Menu.

* Add timeline item menu snapshots for media items.

ElementX/Sources/Screens/Timeline/TimelineInteractionHandler.swift

@@ -102,7 +102,13 @@ class TimelineInteractionHandler {
         case .copy:
             guard let messageTimelineItem = timelineItem as? EventBasedMessageTimelineItemProtocol else { return }
             UIPasteboard.general.string = messageTimelineItem.body
-        case .edit:
+        case .copyCaption:
+            guard let messageTimelineItem = timelineItem as? EventBasedMessageTimelineItemProtocol,
+                  let caption = messageTimelineItem.mediaCaption else {
+                return
+            }
+            UIPasteboard.general.string = caption
+        case .edit, .addCaption, .editCaption, .editPoll:
             switch timelineItem {
             case let messageTimelineItem as EventBasedMessageTimelineItemProtocol:
                 processEditMessageEvent(messageTimelineItem)
@@ -115,13 +121,6 @@ class TimelineInteractionHandler {
             default:
                 MXLog.error("Cannot edit item with id: \(timelineItem.id)")
             }
-        case .addCaption, .editCaption:
-            switch timelineItem {
-            case let messageTimelineItem as EventBasedMessageTimelineItemProtocol:
-                processEditMessageEvent(messageTimelineItem)
-            default:
-                MXLog.error("Cannot add/edit caption on item with id: \(timelineItem.id)")
-            }
         case .removeCaption:
             guard case let .event(_, eventOrTransactionID) = timelineItem.id else {
                 MXLog.error("Failed removing caption, missing event ID")