Update notification settings

Update the organization's notification preferences. These are org-wide, so the change applies to every brand in the organization. All fields optional; only provided fields change. reportRecipients replaces the client-report recipient list (each entry: email + weekly/monthly/whiteLabel booleans + teamIds). weeklyReportTeamIds / monthlyAuditTeamIds scope the org's own reports to specific brands; omit or send null for all brands.