fix(sync): count all files in failed upload batch as failed

[laststylebender14]

Summary

Fix failed_files undercounting when a batch upload fails — a batch of N files was counted as 1 failure instead of N.

Context

The upload stream processes files in batches of up to batch_size. When a batch upload failed, the error handler incremented failed_files += 1 regardless of how many files were in the batch. With a batch size of 100, a single failed batch would only report 1 failed file instead of 100, causing the final SyncProgress::Completed event and the sync error to report incorrect counts.

Changes

• Changed the upload_files stream item type from Result<usize, Error> to (usize, Result<(), Error>), so the batch's attempted file count is always available regardless of success or failure
• Capture attempted = batch.len() before the async block so it's accessible in both the success and failure branches
• On success: counter.complete(attempted) (same as before, now using the tuple)
• On failure: failed_files += attempted instead of += 1

Testing

cargo check -p forge_services