Fix gallery rename applying to wrong files

After renaming a file, loadDirectory() was called which rebuilt the
galleryImages array in new alphabetical order. The gallery index
didn't change, so it now pointed to a different file — subsequent
renames hit the wrong file.

Fix: only update local state during the gallery session, defer the
file list refresh to when the gallery closes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/static/js/filebrowser.js

@@ -291,6 +291,9 @@ const FileBrowser = {
         const img = document.getElementById('gallery-image');
         if (img.src && img.src.startsWith('blob:')) URL.revokeObjectURL(img.src);
         img.src = '';
+
+        // Refresh file list to reflect any renames
+        this.loadDirectory(this.currentPath);
     },
 
     async displayGalleryImage(index) {
@@ -474,9 +477,6 @@ const FileBrowser = {
 
             this.closeRenameModal();
             this.showGalleryToast('File renamed', 'success');
-
-            // Refresh the file list in the background
-            this.loadDirectory(this.currentPath);
         } catch (error) {
             console.error('Error renaming file:', error);
             errorEl.textContent = error.message;