Treat accepted authority as a state-machine invariant, not a metadata flag

Authority may depend on both durable metadata and lifecycle state. If an asynchronous path reopens work by changing status while retaining an acceptance marker, the resolver can stop recognizing authority even though the metadata still looks accepted. Before demoting a parent or a child that inherits its authority, check fresh accepted authority under the same lock that protects the transition.

Applicability and limits: this applies when acceptance and reopening race across asynchronous paths. It is not a universal ban on reopening; intentional revocation needs an explicit product transition and audit semantics rather than an incidental status change.