Non-breaking refactor — buildGuildGossipRpcPullOptsFromRegistry() resolves rpcMethod from the gossip RPC registry for all pull paths; fetchMessageSearchGuildGossipRpcPullByConfig for search mesh; platform-host-rpc-pull-mixin shared by mesh RPC mixin. Mesh sync/member page and search mixins drop manual RPC id wiring. test:ci-phase888 passes (46/50, cutover deferred).