web: open the catalogue without a version another tab can block

docker/frontend/src/Library.tsx

@@ -6,7 +6,6 @@ import {
   getPhoto,
   listEditedIds,
   listFolders,
-  listDirs,
   listPhotos,
   pickFolder,
   readPhotoFile,
@@ -69,8 +68,10 @@ export function Library() {
   const [folders, setFolders] = useState<LibraryFolder[]>([]);
   const [ready, setReady] = useState<Set<string>>(new Set());
   const [photos, setPhotos] = useState<LibraryPhoto[]>([]);
-  // The folders a scan has walked into. A roll's own shape is on screen from the
-  // first pass, before the frames under its folders have been read.
+  // The folders the scan in flight has walked into: a roll's own shape is on
+  // screen from the first pass, before the frames under its folders are read.
+  // What a scan found is not filed away — the next visit draws the folders that
+  // hold frames, and the next scan names the rest again.
   const [dirs, setDirs] = useState<LibraryDir[]>([]);
   const [edited, setEdited] = useState<Set<string>>(new Set());
   // Which tree node is open, which frame is up, and which of the two middle
@@ -111,10 +112,9 @@ export function Library() {
   const [loaded, setLoaded] = useState(false);
 
   const reload = useCallback(async () => {
-    const [rows, edits, dirs] = await Promise.all([listPhotos(), listEditedIds(), listDirs()]);
+    const [rows, edits] = await Promise.all([listPhotos(), listEditedIds()]);
     setPhotos(rows);
     setEdited(edits);
-    setDirs(dirs);
   }, []);
 
   // The catalogue outlives the tab; the permission to read those folders does
@@ -189,6 +189,7 @@ export function Library() {
           folder,
           (p) => {
             setProgress(p);
+            setDirs(p.dirs);
             if (p.done === 0 || Date.now() - last > 700) {
               last = Date.now();
               void reload();
@@ -198,6 +199,7 @@ export function Library() {
           () => jumpRef.current
         );
         setNote(t('lib.scanned', { folder: folder.name, added: result.added, total: result.total }));
+        setDirs(result.dirs);
         await reload();
       } catch {
         setNote(t('lib.failed'));
@@ -257,6 +259,7 @@ export function Library() {
       await removeFolder(folder.name);
       const rest = folders.filter((f) => f.name !== folder.name);
       setFolders(rest);
+      setDirs((prev) => prev.filter((d) => d.folder !== folder.name));
       setNode(rest[0]?.name ?? null);
       await reload();
     },