docs(campaign): document aggregate report baseline

docs/CAMPAIGN_HANDBOOK.md

@@ -144,10 +144,14 @@ paths, storage keys, worker claim tokens, and raw provider diagnostics require
 the dedicated diagnostic permission and must not leak through ordinary campaign,
 version, job, or report responses.
 
-The current Campaign Report Web UI additionally requires recipient-read access
-and does not yet hide every action control that the actor lacks. The server
-still authorizes each action, but an aggregate-only reader UI remains open
-work; do not promise that experience from `campaigns:report:read` alone.
+Campaign now provides a separate aggregate **Reports** surface for readers with
+`campaigns:report:read` and access to the campaign. It loads only the safe
+aggregate projections, applies small-cell suppression, and offers no recipient
+rows, drill-down, filtering, export, or delivery actions. The recipient-aware
+**Campaign Report** still requires recipient-read access and does not yet hide
+every action control that the actor lacks. The server authorizes each action,
+but permission-aware action visibility on that detailed surface remains open
+work; do not confuse it with the aggregate reader experience.
 
 ### Deliver and resolve outcomes