[DeckShare] Abandon an in-flight tile share on cancel

exitShareMode() left shareTimeoutTimer running and did not abandon the pending
Command_DeckShareCreate, so a timer pop or a late success still reported the
share after the user cancelled. Stop the timer and ignore stale responses via a
sequence number, mirroring the tree tab.

cockatrice/src/interface/widgets/tabs/visual_deck_storage/tab_deck_storage_visual.cpp

@@ -103,6 +103,10 @@ void TabDeckStorageVisual::enterShareMode(const QStringList &preselectFiles)
 
 void TabDeckStorageVisual::exitShareMode()
 {
+    // Abandon any in-flight request: otherwise the timer keeps running and a late
+    // response reports the share as created after the user already backed out.
+    shareTimeoutTimer->stop();
+    shareInFlightSeq = 0;
     visualDeckStorageWidget->setShareSelectable(false);
     visualDeckStorageWidget->clearShareSelection();
     shareBar->setVisible(false);
@@ -165,8 +169,17 @@ void TabDeckStorageVisual::actShareSelected()
     }
 
     shareBar->setCreateEnabled(false);
+    const int seq = ++shareRequestSeq;
+    shareInFlightSeq = seq;
     PendingCommand *pend = client->prepareSessionCommand(cmd);
-    connect(pend, &PendingCommand::finished, this, &TabDeckStorageVisual::shareFinished);
+    connect(pend, &PendingCommand::finished, this,
+            [this, seq](const Response &response, const CommandContainer &commandContainer) {
+                if (shareInFlightSeq != seq) {
+                    return; // the user cancelled or a newer request superseded this one
+                }
+                shareInFlightSeq = 0;
+                shareFinished(response, commandContainer);
+            });
     client->sendCommand(pend);
     shareTimeoutTimer->start();
 }
@@ -207,6 +220,10 @@ void TabDeckStorageVisual::showShareNotice(const QString &message, bool warning)
 
 void TabDeckStorageVisual::onShareTimeout()
 {
+    if (shareInFlightSeq == 0) {
+        return; // share mode was left while the request was still outstanding
+    }
+    shareInFlightSeq = 0;
     shareBar->setCreateEnabled(true);
     showShareNotice(tr("The server did not respond in time. Try again."), true);
 }

cockatrice/src/interface/widgets/tabs/visual_deck_storage/tab_deck_storage_visual.h

@@ -77,6 +77,8 @@ private:
     ShareBarWidget *shareBar;
     AbstractClient *client;
     QTimer *shareTimeoutTimer;
+    int shareRequestSeq = 0;
+    int shareInFlightSeq = 0;
     bool shareDeckAvailable = false;
 };