GuildUpdateTask.Parse() reads data[guild] as GuildDetailInfo directly; the previous
GuildDetailSubTree wrapper (data[guild][detail]) caused json[guild_id].ToInt() to
crash on the client. Split GuildUpdateResponse (flat) from GuildUpdateEmblemResponse
(nested, correct for GuildEmblemUpdateTask.Parse). Also surfaces guild_name from the
request through UpdateGuildRequest.Name -> service -> repo so the client rename is honoured.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>