[Oracle] Don't report a cancelled card database update as successful (#7082)

* [Oracle] Don't report a cancelled card database update as successful (#3470)

Took 3 minutes

* [Oracle] Only report cancel when nothing was saved yet

Rejecting the wizard after SaveSetsPage or a download page already
wrote the database to disk still replaced cards.xml on disk, but
wasCancelled() forced exit code 1 so Cockatrice skipped the reload.
Track successful saves with OracleWizard::markDatabaseSaved() and only
treat a cancel as a failure when nothing was saved.

* [Oracle] Restore updater stderr in card update error dialog

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Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

oracle/src/main.cpp

@@ -85,5 +85,8 @@ int main(int argc, char *argv[])
         QTimer::singleShot(0, &wizard, [&wizard]() { wizard.runInBackground(); });
     }
 
-    return app.exec();
+    const int execResult = app.exec();
+    // A cancel only counts when nothing was written yet: closing the wizard
+    // after the card database was already saved on disk is still an update.
+    return (wizard.wasCancelled() && !wizard.hasSavedDatabase()) ? 1 : execResult;
 }