c1b3ba1c34
Buckets could not choose which RGW placement target (and thus durability profile) backs them, so all data landed on the cluster default. The estate's radosgw exposes two targets - default-placement (3x replicated) and ec (4+1 erasure-coded) - and archival workloads want ec. - Validate spec.placementTarget: a DNS-ish pattern, 63-char cap, and a CEL self==oldSelf immutability rule (RGW fixes placement at bucket creation and cannot move a bucket between targets); make spec.zonegroup immutable too. - Thread the target into the S3 CreateBucket LocationConstraint via the existing helper; an empty zonegroup yields ":<target>", selecting the local zonegroup so callers need not name the zonegroup api-name. - Read the live placement_rule and zonegroup back from the Admin Ops bucket stats and surface them: status.placementTarget plus a Placement print column. - Guard the controller: if a live bucket's placement differs from spec, set an Error phase with a PlacementImmutable reason instead of deleting/recreating. - Cover locationConstraint construction, placement readback (httptest), and the placementConflict guard with tests; document targets and immutability in the README and add config/samples/06-bucket-ec.yaml. Claude-Session: https://claude.ai/code/session_015ur3i7D2azsMAWTSVABApv