master
build: ignore revive lint issue var-naming: avoid meaningless package names
build: remove x := x made unnecessary by the new semantics of loops in go1.22
fs: define the optional interface SetMetadata and implement it in wrapping backends
cache,chunker,combine,compress,crypt,hasher,union: implement MkdirMetadata and related Features
union: allow errors to be unwrapped for inspection
build: update to go1.23rc1 and make go1.21 the minimum required version
union: mark ListP as not supported yet
local: add server-side copy with xattrs on macOS (part-fix #1710)