v1.0.0-rc.21

A set of API 2.25 features and a number of optimizations affecting all
applications using NeoFS.

New features:

• io.WriterTo interface support for object payload reader avoiding data copy (#818)
• Extended range parameter for object GET (#826)
• EACL record comment field support (#832)
• Slicer callback to adjust header before sealing an object (#830)
• io.ReaderFrom implementation for object payload writer avoiding data copy (#827)

Behaviour changes:

• Response info callback deleted from client (#822)
• EC chunk objects no longer require signature (#830)
• SignerV2 interface removed from crypto library (#836)
• Origin signatures are no longer generated/checked for API 2.25+ requests (#833, #841)
• Client uses server API version if it's lower than the latest SDK version (#833)
• API v2.25 used by default (#841)

Improvements:

• Updated golang.org/x/net dependency from 0.50.0 to 0.55.0 (#820)
• Updated golang.org/x/crypto dependency from 0.51.0 to 0.52.0 (#825)
• Updated NeoGo dependency from 0.118.0 to 0.121.0 (#823)
• Updated google.golang.org/grpc dependency from 1.79.3 to 1.82.1 (#834)
• Object payload reader makes one data copy less (#835)
• More effective GET/SEARCH/HEAD request encoding (#824, #838)

Bugs fixed:

• Missing EC part hashes attribute definition (#840)