`uploadFiles` sent files one at a time (await per file), so dropping N
files meant N sequential round-trips. Reuse the bounded-concurrency pool
already proven in `uploadFolderEntries` (CONCURRENCY = 10): independent
files now upload up to 10 at a time — ~10x faster for many small files.
Per-file progress (XHR → bell), the legacy progress bar, timeout
notifications and the quota short-circuit are preserved. On a quota error
the pool stops pulling new files while in-flight uploads finish (matching
`uploadFolderEntries`) instead of the old hard `break`.
https://claude.ai/code/session_01Dp3oWon5GBMVn4j3QXZdgx
Claude
3c64354a0d