fileitemaction: use ::rename() instead of QFile::rename()

QFile::rename() silently falls back to copy+delete. POSIX rename(2)
is always atomic on the same filesystem.

fileitemaction/denote_fileitemaction.cpp

@@ -12,6 +12,7 @@
 #include <QDir>
 #include <QFile>
 #include <QFileInfo>
+#include <cstdio>
 #include <QFormLayout>
 #include <QLineEdit>
 #include <QScreen>
@@ -130,8 +131,8 @@ void DenoteFileItemAction::renameWithDenote(const KFileItemList &items, QWidget
     const QString newName = Denote::buildFilename(title, tags, signature, ext);
     const QString newPath = fi.dir().filePath(newName);
 
-    // Rename
-    QFile::rename(path, newPath);
+    // Rename (use ::rename for atomic, no-copy behavior)
+    ::rename(path.toLocal8Bit().constData(), newPath.toLocal8Bit().constData());
 
     // Update frontmatter if supported
     if (fileType != Denote::FileType::Unknown) {