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

README.md

@@ -91,8 +91,10 @@ yarn build
 QUAK_EMAIL=… QUAK_PASSWORD=… node dist/examples/download-albums.js [dir]
 ```
 
-It asks on the terminal for a two-factor or email code when the account requires
-one, and writes:
+It opens the library with `precacheThumbnails` and `precacheOriginals` off, as
+`quak backup` does, so the only file content it fetches is the originals it
+saves. It asks on the terminal for a two-factor or email code when the account
+requires one, and writes:
 
 - each photo's original at its save path under `dir`, as `photo.download()`
   writes it: `YYYY/YYYY-MM/YYYY-MM-DD/YYYY-MM-DD.<fileID>.<ext>`, and for a live