[LyX/master] Fix missing initialization spotted by Coverity Scan

[Jean-Marc Lasgouttes]

commit 8b29adbef258e35c9773e6656a2d547d4330f37e
Author: Jean-Marc Lasgouttes <lasgouttes at lyx.org>
Date:   Mon Sep 7 15:18:38 2026 +0200

    Fix missing initialization spotted by Coverity Scan
---
 src/TextClass.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/TextClass.h b/src/TextClass.h
index e7ec8b6b77..e8d054784c 100644
--- a/src/TextClass.h
+++ b/src/TextClass.h
@@ -220,7 +220,7 @@ public:
 		///
 		docstring submenu;
 		///
-		bool use_counters;
+		bool use_counters = false;
 	};
 	/// Does this class provide \forntmatter, \mainmatter, and \backmatter?
 	bool hasMatter(std::string const & m) const;