Give DelegateContextMenu an actual room

This allows me to hide the "Reply" action for read-only rooms. Don't ask
me how it even worked before, I don't know.

src/app/qml/RoomPage.qml

@@ -349,8 +349,9 @@ Kirigami.Page {
             });
         }
 
-        function onShowDelegateMenu(parent: QtObject, eventId: string, author, messageComponentType, plainText: string, richText: string, mimeType: string, progressInfo, selectedText: string, hoveredLink: string) {
+        function onShowDelegateMenu(parent: QtObject, room: NeoChatRoom, eventId: string, author, messageComponentType, plainText: string, richText: string, mimeType: string, progressInfo, selectedText: string, hoveredLink: string) {
             (delegateContextMenu.createObject(parent, {
+                room: room,
                 author: author,
                 eventId: eventId,
                 plainText: plainText,

src/app/roommanager.cpp

@@ -290,6 +290,7 @@ void RoomManager::viewEventMenu(QObject *parent, const RoomEvent *event, NeoChat
     }
 
     Q_EMIT showDelegateMenu(parent,
+                            room,
                             event->id(),
                             room->qmlSafeMember(event->senderId()),
                             MessageComponentType::typeForEvent(*event),

src/app/roommanager.h

@@ -308,6 +308,7 @@ Q_SIGNALS:
      * @brief Request to show a menu for the given event.
      */
     void showDelegateMenu(QObject *parent,
+                          NeoChatRoom *room,
                           const QString &eventId,
                           const NeochatRoomMember *author,
                           MessageComponentType::Type messageComponentType,

src/timeline/DelegateContextMenu.qml

@@ -159,7 +159,7 @@ KirigamiComponents.ConvergentContextMenu {
 
     Kirigami.Action {
         id: replyAction
-        visible: root.messageComponentType !== MessageComponentType.Other || NeoChatConfig.relateAnyEvent
+        visible: !root.room.readOnly && (root.messageComponentType !== MessageComponentType.Other || NeoChatConfig.relateAnyEvent)
         text: i18nc("@action:inmenu", "Reply")
         icon.name: "mail-replied-symbolic"
         onTriggered: {