Fix-up ImageComponent's hide media functionality

The Z-level for the "Hide media" and other overlay controls were lost
during the rich text refactor, and now restored. I also made it so the
blurhash is now used when the media is hidden, and when hiding media it
no longer allows you to jumpscare yourself by maximizing the media when
you probably didn't actually want to.

When the media doesn't have blurhash, it falls back to black.

src/messagecontent/ImageComponent.qml

@@ -66,8 +66,9 @@ Item {
         anchors.right: root.right
         anchors.rightMargin: root.rightAnchorMargin + Kirigami.Units.smallSpacing
 
-        QQC2.Button {
+        z: 10
 
+        QQC2.Button {
             visible: !_private.hideImage && !root.editable
             icon.name: "view-hidden"
             text: i18nc("@action:button", "Hide Image")
@@ -119,6 +120,30 @@ Item {
         }
     }
 
+    Rectangle {
+        anchors.fill: parent
+
+        visible: (_private.imageItem?.status !== Image.Ready ?? true) || _private.hideImage
+
+        color: "#BB000000"
+
+        QQC2.ProgressBar {
+            anchors.centerIn: parent
+
+            width: parent.width * 0.8
+            visible: !_private.hideImage
+
+            from: 0
+            to: 1.0
+            value: _private.imageItem?.progress ?? 0.0
+        }
+
+        Image {
+            anchors.fill: parent
+            source: root?.componentAttributes.tempInfo?.source ?? ""
+        }
+    }
+
     Loader {
         id: imageLoader
 
@@ -151,12 +176,6 @@ Item {
         }
     }
 
-    Image {
-        anchors.fill: parent
-        source: visible ? (root?.componentAttributes.tempInfo?.source ?? "") : ""
-        visible: _private.imageItem && _private.imageItem.status !== Image.Ready && !_private.hideImage
-    }
-
     QQC2.ToolTip.text: root.display
     QQC2.ToolTip.visible: hoverHandler.hovered
     QQC2.ToolTip.delay: Kirigami.Units.toolTipDelay
@@ -165,26 +184,6 @@ Item {
         id: hoverHandler
     }
 
-    Rectangle {
-        anchors.fill: parent
-
-        visible: _private.imageItem.status !== Image.Ready || _private.hideImage
-
-        color: "#BB000000"
-
-        QQC2.ProgressBar {
-            anchors.centerIn: parent
-
-            width: parent.width * 0.8
-            visible: !_private.hideImage
-
-            from: 0
-            to: 1.0
-            value: _private.imageItem.progress
-        }
-
-    }
-
     QQC2.Button {
         anchors.centerIn: parent
         text: i18nc("@action:button", "Show Image")
@@ -206,7 +205,7 @@ Item {
             if (root.Message.timeline) {
                 root.Message.timeline.interactive = false;
             }
-            if (!root.componentAttributes.isSticker && !root.editable) {
+            if (!root.componentAttributes.isSticker && !root.editable && !_private.hideImage) {
                 RoomManager.maximizeMedia(root.eventId);
             }
         }