Update an Audience name and sharing settings

Renames an Audience and optionally changes its visibility. name is required on every call; isPublic and isSharedWithTeam are applied only when sent as booleans and left unchanged otherwise. isLinkSharingEnabled cannot be changed here (it is echoed in the response). Allowed for collaborators: the owner, direct members, and members of the owner's team when the Audience is team-shared. Only the owner may change isSharedWithTeam (403 TEAM_SHARE_OWNER_ONLY otherwise), and sharing requires the owner to be in a team (400 TEAM_REQUIRED). Public and Study-link viewers receive 404. Setting isSharedWithTeam: true lets every member of the owner's team open the Audience and read and chat with every Mind in it, even when those Minds are not shared individually; it grants no edit rights on the Minds. Explicit Audience members get the same read access. Setting isPublic: true lists the Audience in the marketplace and queues a cover image for it.