feat(platform): Phase 880 host-prefer RPC pull + search merge (v0.8.847)
Non-breaking refactor: fetchGuildGossipRpcFromHostHit for guild sync and
member page mesh pulls; fetchGuildGossipRpcPullMerged with
mergeGuildMessageSearchRpcHits for search; prepareGuildGossipRpcFanoutRequest
dedupes fanout prep shared by pick-first and merge paths. Default gossip v1
unchanged; fleet v2 cutover deferred.
Tests: test:ci-phase880 (boot gate, unit, view snapshot, method maps, live search RPC).
Docs: PLATFORM_ROADMAP, PROTOMUX_RPC_MIGRATION, AUTOMATED_TESTING, release notes.
Raven Scott
eba01c1151