fix(library): resolve root folder rename, open in explorer, open at location centering, UPDATE rescan bug, and optimize scan RAM memory usage

docker/frontend/src/engine/library.ts

@@ -146,7 +146,7 @@ export function canBrowseFolders(): boolean {
   return typeof window !== 'undefined' && 'showDirectoryPicker' in window;
 }
 
-const THUMB_CACHE_MAX = 5000;
+const THUMB_CACHE_MAX = 800;
 const thumbCache = new Map<string, Blob>();
 
 export function cacheThumb(id: string, blob: Blob): void {
@@ -729,7 +729,13 @@ export async function scanFolder(
   // frames it does not re-read are skipped on their size and their time.
   const bounded = from !== '';
   const saved = bounded ? null : await loadWalk(folder.name);
-  const tree: Walk = { root: folder.handle, pending: [], walked: new Set(saved?.walked ?? []) };
+  const treeWalked = new Set(saved?.walked ?? []);
+  if (from) {
+    for (const p of [...treeWalked]) {
+      if (p === from || p.startsWith(from)) treeWalked.delete(p);
+    }
+  }
+  const tree: Walk = { root: folder.handle, pending: [], walked: treeWalked };
   // A queue comes back as paths, so the folders are asked for again; a reading
   // with nothing written down starts at the folder it was pointed at — the
   // picked one, or the one the reader right-clicked inside it.
@@ -738,6 +744,10 @@ export async function scanFolder(
       const dir = await openAt(folder.handle, rel);
       if (dir) tree.pending.push({ dir, rel });
     }
+    if (from && !tree.pending.some((p) => p.rel === from)) {
+      const dir = await openAt(folder.handle, from);
+      if (dir) tree.pending.unshift({ dir, rel: from });
+    }
   } else {
     const dir = from ? await openAt(folder.handle, from) : folder.handle;
     if (dir) tree.pending.push({ dir, rel: from });
@@ -991,9 +1001,8 @@ export async function scanFolder(
         progress.done++;
         count(rel);
       }
-      // A RAW takes the one open there is before its lane does anything, so a
-      // folder of them is read a frame at a time whatever the lanes say.
-      const read = isRawName(handle.name) ? oneRawAtATime(() => readOne(handle, rel)) : readOne(handle, rel);
+      // Queue image decoding one at a time so memory usage stays low and UI stays smooth
+      const read = oneRawAtATime(() => readOne(handle, rel));
       const lane = read
         .catch(() => undefined)
         .finally(() => lanes.delete(lane));