* fix: correctly detect missing source file during volume copy
The previous fix (commit 5c27522) incorrectly used progressedBytes == 0 to
detect if the source file didn't exist. This was wrong because it would also
delete files when the source file exists but is empty.
This fix:
1. Server side: Send ModifiedTsNs even for empty files, so the client knows
the source file exists
2. Client side: Check modifiedTsNs == 0 instead of progressedBytes == 0 to
determine if source file didn't exist
Now the logic correctly handles:
- Source file doesn't exist → No ModifiedTsNs sent → Remove empty file
- Source file exists but is empty → ModifiedTsNs sent → Keep empty file
- Source file exists with content → ModifiedTsNs sent → Keep file with content
Fixes#7777
* Update weed/server/volume_grpc_copy.go
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
---------
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
ef28f49ec3