CAT-MS1, CAT-MS2: offered and closed carry the operator-channel definition's fields (id, asker, headline, channels; id, asker, how); the page reads them

The test of the five ends holds every key of a body to the seat definition's holder events, so the router and the contract cannot drift.

Issue 1968.

Claude-Session: https://claude.ai/code/session_01JG73KJNrH5EgFXMKKYSrig

modules/mesh-knowledge/cmd/mesh-knowledge/overview.go

@@ -398,9 +398,10 @@ func (o *Overview) Heard(source, event string, body json.RawMessage) {
 	case SourceAsks:
 		switch name {
 		case "offered":
-			o.asks[f.Key] = askRow{Key: f.Key, Asker: f.Asker, Headline: f.Headline, Offered: firstStrings(f.Offered, f.Channels)}
+			k := firstNonEmpty(f.Key, f.Asker+"."+f.ID)
+			o.asks[k] = askRow{Key: k, Asker: f.Asker, Headline: f.Headline, Offered: firstStrings(f.Offered, f.Channels)}
 		case "closed":
-			delete(o.asks, f.Key)
+			delete(o.asks, firstNonEmpty(f.Key, f.Asker+"."+f.ID))
 		}
 	}
 	o.rebuilt = o.now()