* ec: carry the source volume's TTL expiry into the worker-written .vif
ReadVolumeFileStatus now reports the volume's ExpireAtSec (last write +
TTL), and the admin worker stamps it into the .vif it distributes with
the shards. Previously every worker-encoded .vif had expireAtSec 0, so
EC volumes of TTL collections never expired.
* ec: report expiry from the Rust volume server and cover the .vif carry
The seaweed-volume drop-in server omitted expire_at_sec from its
ReadVolumeFileStatus response, so worker-encoded volumes sourced from it
lost the TTL. Fall back to the nested VolumeInfo expiry for servers that
predate the top-level field, and pin the nonzero/zero carry with a test.
Chris Lu
887b1aac76