downloadTimeoutMs now aborts a file or thumbnail download only when no
bytes have arrived for that long (default 60 s, was a 600 s cap on the
whole transfer), so a slow download that keeps making progress completes.
The abort reason is still a TimeoutError, so retry classification is
unchanged. A download that fails before reading the whole response body
cancels it, including when the temp file cannot be opened or the header
is malformed, so a failed file no longer holds its connection.
Model: opus-5-5
sneak