TempInfo Messageeventmodel

Further improvements to the handling of `mediaInfo` in `messageeventmodel`.

`blurhash` and `thumbnailInfo` are now replaced with a single `tempInfo` object that contains a single temp source. The priority is thumbnail > `blurhash` > empty if none exist.

Fixes network/neochat#235

src/qml/Component/NeochatMaximizeComponent.qml

@@ -20,7 +20,7 @@ Components.AlbumMaximizeComponent {
         Components.AlbumModelItem {
             type: root.modelData.delegateType === MessageEventModel.Image || root.modelData.delegateType === MessageEventModel.Sticker ? Components.AlbumModelItem.Image : Components.AlbumModelItem.Video
             source: root.modelData.delegateType === MessageEventModel.Video ? modelData.progressInfo.localPath : modelData.mediaInfo.source
-            tempSource: modelData.mediaInfo.blurhash
+            tempSource: modelData.mediaInfo.tempInfo.source
             caption: modelData.display
         }
     ]

src/qml/Component/Timeline/ImageDelegate.qml

@@ -74,7 +74,7 @@ TimelineContainer {
 
         Image {
             anchors.fill: parent
-            source: model.mediaInfo.blurhash
+            source: model.mediaInfo.tempInfo.source
             visible: parent.status !== Image.Ready
         }
 

src/qml/Component/Timeline/VideoDelegate.qml

@@ -154,7 +154,7 @@ TimelineContainer {
             anchors.fill: parent
             visible: false
 
-            source: model.mediaInfo.thumbnailInfo.source
+            source: model.mediaInfo.tempInfo.source
             fillMode: Image.PreserveAspectFit
         }