fix: realtime folder photo counts during scan discovery and decode

docker/frontend/src/engine/library.ts

@@ -809,6 +809,17 @@ export async function scanFolder(
     }
   };
   for (const id of known.keys()) count(id.startsWith(`${normRoot}/`) ? id.slice(normRoot.length + 1) : id);
+  const knownPaths = new Set(
+    [...known.keys()].map((id) => (id.startsWith(`${normRoot}/`) ? id.slice(normRoot.length + 1) : id))
+  );
+  const countedDiscovered = new Set<string>();
+  const countDiscovered = (rel: string) => {
+    const relClean = rel.replace(/\\/g, '/');
+    if (knownPaths.has(relClean) || countedDiscovered.has(relClean)) return;
+    countedDiscovered.add(relClean);
+    count(relClean);
+  };
+  for (const e of entries) countDiscovered(e.rel);
   // The frames the catalogue already holds of the folder being read, which is
   // what the reading is measured against: a roll of a hundred thousand that has
   // been read once before is a reading of a hundred thousand frames even while
@@ -1036,10 +1047,20 @@ export async function scanFolder(
       // through. A jump would take it out of the subtree it was kept to, and
       // the reading it left behind is the reading that folder wanted.
       const asked = bounded ? () => null : (jump ?? (() => null));
-      walked = await walkPass(tree, entries, names, isSupportedPhoto, asked, (dirRel) => {
-        progress.at = normPath(dirRel);
-        publish(true);
-      });
+      walked = await walkPass(
+        tree,
+        entries,
+        names,
+        isSupportedPhoto,
+        asked,
+        (dirRel) => {
+          progress.at = normPath(dirRel);
+          publish(true);
+        },
+        (file) => {
+          countDiscovered(file.rel);
+        }
+      );
       // The names come in before the frames they hold: the column grows one pass
       // ahead of the strip, which is the whole point of reading layer by layer.
       for (const rel of names) {

docker/frontend/src/engine/rollWalk.ts

@@ -88,7 +88,8 @@ export async function walkPass(
   seen: string[],
   keep: (name: string) => boolean,
   jump: () => string | null,
-  onDir?: (rel: string) => void
+  onDir?: (rel: string) => void,
+  onFile?: (file: WalkFile) => void
 ): Promise<boolean> {
   for (let i = 0; i < DIRS_PER_PASS && walk.pending.length; i++) {
     await jumpQueue(walk, jump());
@@ -107,7 +108,9 @@ export async function walkPass(
           walk.pending.push({ dir: entry as FileSystemDirectoryHandle, rel });
           seen.push(rel);
         } else if (keep(entry.name)) {
-          out.push({ handle: entry as FileSystemFileHandle, rel: `${baseRel}${entry.name}` });
+          const file: WalkFile = { handle: entry as FileSystemFileHandle, rel: `${baseRel}${entry.name}` };
+          out.push(file);
+          onFile?.(file);
         }
       }
     } catch {