feat(reporting): top sender domains and top spam sources (client IPs) on the Reporting page — two new cards show the most active sender domains and most aggressive client IPs with spam and rejected counters; time window selectable as 7/14/30 days; data aggregated cluster-wide (1.50.96)
feat(reporting): spam analytics dashboard — score distribution as inline bar chart (2-point bands color-coded by severity), near-threshold sender domains (score 4–10), and false-negative list from the audit log; time window selectable as 24h/72h/7d (1.50.96)