Update study link and team sharing

Owner only. isLinkSharingEnabled enables or disables the public link; enabling it also exposes the attached Audiences and Minds, matching the web app. isSharedWithTeam: true lets every current and future member of the owner's team open the Study (team viewers read only); it sends no invitation or notification, and false removes that access at once. Sharing with the team requires the owner to be in a team (400 TEAM_REQUIRED). Send either field or both.