Integrate the new S3 checksum types in the gateway, including `SHA512`, `MD5`, `XXHASH64`, `XXHASH3`, and `XXHASH128`. This adds checksum calculation, validation, schema handling, and test coverage for the expanded checksum support.
These external packages have been used:
- `github.com/zeebo/xxh3` for `XXHASH3` and `XXHASH128`
- `github.com/cespare/xxhash/v2` for `XXHASH64`
Adjust integration tests because `aws-sdk-go-v2/service/s3` does not support automatic checksum calculation for the new checksum algorithms and returns an SDK-level error when only the checksum algorithm is provided. Only precalculated checksum values are acceptable for these checksum types.
References:
- `https://github.com/aws/aws-sdk-go-v2/issues/3404`
- `https://github.com/aws/aws-sdk-go-v2/issues/3403`
As multipart uploads are translated to blobs in azure blob storage, they were visible in ListObjects(V2) as complete objects. Now the blobs with multipart prefix are filtered out during listing.
The listing logic is rewritten client-side to implement proper S3 semantics: flat blob enumeration with manual delimiter handling, correct truncation (IsTruncated only set when more items genuinely exist beyond maxKeys), and StartAfter/Marker/ContinuationToken applied via the lexicographic max of both constraints in ListObjectsV2.
For the same reason bucket deletion was not allowed. Now multipart objects are explicitly checked on bucket deletion and any pending multipart upload doesn't block the bucket deletion anymore.
All the integration tests used to be in a single file, which had become large, messy, and difficult to maintain. These changes split `tests.go` into multiple files, organized by logical test groups.
niksis02