[Enhancement] UploadPartCopy performance baseline

[superhx]

When the size of the source object that the stream object compact wants to merge is too large, UploadPartCopy will take more than 30 seconds, causing a timeout.
Action:

• Adjust the stream object compact max size temporarily to work around the issue; #792
• Benchmark the performance baseline of UploadPartCopy;
• Isolate DefaultS3Operator S3 SDK to provide longer timeouts for background tasks;
• Automatically split large UploadPartCopy into more reasonable sizes to ensure completion within API timeouts.