download-albums example: walk the albums from lib.fresh()

downloadAlbums now waits for a refresh from the server through lib.fresh()
before walking the albums, so albums and photos added since the cache was
last written are downloaded, and a failed refresh throws instead of
reporting an empty or stale library as done. The test's stand-in account
gains an album holding a new photo before the second run, and that run must
download it. The README's "Examples" section says the script opens the
library with the thumbnail and originals precache off, as `quak backup` does.

Model: opus-5-5

examples/download-albums.ts

@@ -36,7 +36,10 @@ export async function downloadAlbums(
     let alreadyLocal = 0;
     // A photo in several albums is handled once.
     const done = new Set<number>();
-    for (const album of lib.albums.list()) {
+    // fresh() waits for a refresh from the server and throws if it fails, so
+    // albums and photos added since the cache was last written are included.
+    const { albums } = await lib.fresh();
+    for (const album of albums.list()) {
         const savePaths: string[] = [];
         for (const photo of album.photos.list()) {
             if (!done.has(photo.fileID)) {