BF: Set explicit timeout for zarr chunk upload PUT requests

Previously, zarr chunk uploads used no explicit timeout, relying on OS
TCP defaults.  For large zarr chunks (e.g., 2.6 GB level-0 OME-Zarr
chunks), the upload can take many minutes at typical home upload speeds
(~7 min at 50 Mbps, ~70 min at 5 Mbps).  Without a timeout, the client
either hangs indefinitely on network failures, or the OS TCP stack's
default keepalive/idle timeout (often ~120s on Windows) kills the
connection before a large upload can complete.

Set an explicit requests timeout of (60, 7200) — 60 seconds for TCP
connect, 2 hours for response read.  The read timeout covers the period
after the full request body is sent while waiting for S3's response,
which is where ConnectionAbortedError was observed in #1821.

Note: this does NOT limit the upload body transfer time itself.  The
requests library's read timeout only applies to waiting for response
data, not to sending request data.  So even very slow multi-hour uploads
will not be interrupted by this timeout.

Ref: #1821

Co-Authored-By: Claude Code 2.1.81 / Claude Opus 4.6 <noreply@anthropic.com>

Author: yarikoptic

dandi/files/zarr.py

@@ -969,6 +969,7 @@ def _upload_zarr_file(
                 json_resp=False,
                 retry_if=_retry_zarr_file,
                 headers=headers,
+                timeout=(60, 7200),
             )
     except requests.HTTPError as e:
         post_upload_size_check(item.filepath, item.size, True)