[LyX/master] Update ja.po

[Koji Yokota]

commit 4c5dd9389301ac80455823dd897f83c38869904e
Author: Koji Yokota <yokota at lyx.org>
Date:   Thu Aug 6 23:50:49 2026 +0900

    Update ja.po

 po/ja.po | 2968 ++++++++++++++++++++++++++++++++++----------------------------
 1 file changed, 1626 insertions(+), 1342 deletions(-)