Set the v1.6.24 session, cookie, and cache contract

[salasebas]

Question

For the Better Auth v1.6.24 deltas covering authoritative-session checks, cookie-cache expiry and revocation, secure-cookie precedence, parsing and serialization, refresh propagation, session/account cookie chunking, stateless expiry, Max-Age, Set-Cookie deduplication, and get-session no-store headers, what exact RustAuth wire and storage contract should ship? Record any intentional divergence and the cross-adapter and framework evidence required.