First systematic HTTP e2e batch for the admin management surface
(backlog#1154 peri-2): full user -> canned-policy -> attach ->
service-account lifecycle with data-plane effect assertions (the
credential really gains and loses S3 access), plus a non-admin 403
probe per management endpoint targeting a different principal so
deny_only self-access semantics do not mask the gate. Wired into the
e2e-smoke nextest profile (ci-4 mechanism).
Zhengchao An