[LyX/master] Safeguard inset definition in case the include chain would break.

[Pavel Sanda]

commit 130ad20bee006adeccd08796c780911e3726af2f
Author: Pavel Sanda <sanda at lyx.org>
Date:   Sun Sep 6 01:44:43 2026 +0200

    Safeguard inset definition in case the include chain would break.
    
    Claude's audit shows that all other forward decl pointers in signal/slot
    are are used only in same-thread (direct) connections.
    
    Offshoot of https://marc.info/?l=lyx-devel&m=178859790774691&w=2
---
 src/frontends/qt/GuiView.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/frontends/qt/GuiView.cpp b/src/frontends/qt/GuiView.cpp
index c199faebc8..40a5744947 100644
--- a/src/frontends/qt/GuiView.cpp
+++ b/src/frontends/qt/GuiView.cpp
@@ -89,6 +89,10 @@
 #include "support/Timeout.h"
 #include "support/ProgressInterface.h"
 
+// Queued signals need full definition (compiles, but fails at runtime). showDialog
+// called from export thread is executed on the GUI thread via triggerShowDialog.
+#include "insets/Inset.h"
+
 #include <QAction>
 #include <QApplication>
 #include <QCloseEvent>