scaleway/object-bucket v4.0.0

Renames object-bucket's namespace/name inputs to name_prefix/name_suffix, matching the convention ADR-0118 already applied to compute-instance — same "${var.name_prefix}-${random_string.suffix.result}-${var.name_suffix}" naming scheme, just call-site names that read correctly (name_prefix = "job-${local.namespace}" instead of pairing a generic namespace variable with an already-namespace-shaped value).

Also flips storage_class's default from "standard" to "glacier". Nearly every real consumer of this module is cold/archival data (poisoned/*, email, media, macbook-scratch, backblaze), so the new default matches what most callers actually want instead of requiring each to opt in by hand.

Both changes are breaking: existing callers must rename their namespace/name arguments, and any caller relying on the implicit "standard" default now needs to set storage_class = "standard" explicitly to keep that behavior.

See docs/adr/0119-decouple-scaleway-iam-application-api-key-rename-object-bucket.md for the full decision record (this PR covers only the object-bucket half of that ADR).

#161