feat(mirror): warn when `repo mirror create` hits an admin-suspended mirror

When create re-registers an existing placement that an admin has suspended, it now prints a warning right after the placement message:

It skips the pointless clone-readiness poll (a suspended mirror never becomes ready) and treats the re-create as a non-fatal success (exit 0) — the warning, not a hard error. The wizard surfaces the same state as a "suspended" status per mirror.

Consumes the new suspended field on the CreatedMirror response; spec + regenerated coreapi client updated to match.