Page an answer larger than one message of the bus, and keep overviews brief (hq issue 314)

The client library refuses to send a reply over the bus's max_payload, and the
controller only logged it: conditions and status answered nobody for hours on
2026-10-08 while calls said each was answered in 130 ms, and the operator's
channel read nothing. An answer too large is now held under its call and paged
to the caller that asks, on the same subject; a caller that does not page is
told in words, and calls says it. The overviews no longer carry every finding:
conditions and status list each condition with its newest evidence, doctor at
most twenty findings a probe (probe= gives one whole), and the JSON overviews
are sent once, as data, instead of twice.

cmd/mesh-controller/readable.go

@@ -91,8 +91,8 @@ type meshStatus struct {
 	// Conditions is every open condition, urgent first and then oldest first (novox/hq to-be 45 §2):
 	// what is wrong, as the watchdogs, the self-check and the providers say it. Always present — an
 	// empty list is "none open" — unless they could not be read, which ConditionsUnread says.
-	Conditions       []conditions.Condition `json:"conditions"`
-	ConditionsUnread string                 `json:"conditionsUnread,omitempty"`
+	Conditions       []conditionInBrief `json:"conditions"`
+	ConditionsUnread string             `json:"conditionsUnread,omitempty"`
 	// Failing is every consumer a provider says it keeps failing (novox/hq ADR 0224): the open
 	// conditions of that kind, carried here as well because ADR 0224 names this field. Absent when no
 	// provider says so. A document without it called the mesh well while the identity provider
@@ -235,10 +235,9 @@ func statusAsJSON(asked answers) ([]byte, error) {
 	out.Unheld = asked.unheld
 	out.HandActsThisWeek, out.HandActsUnread = asked.handActs, asked.handActsUnread
 	out.HealsThisWeek, out.HealsUnread = asked.heals, asked.healsUnread
-	out.Conditions, out.ConditionsUnread = asked.conditions, asked.conditionsUnread
-	if out.Conditions == nil {
-		out.Conditions = []conditions.Condition{}
-	}
+	// In brief, as `conditions` lists them: status leads with every open condition, and their whole
+	// evidence is each one's own (novox/hq issue 314).
+	out.Conditions, out.ConditionsUnread = inBrief(asked.conditions), asked.conditionsUnread
 	out.Failing = providerStandings(asked.conditions)
 	out.Overflowing = asked.overflowing
 	for name := range asked.refused {