The controller no longer subscribes to the alive message: HostBeats, its handler, the heartbeat-gap duration and a fixed silent bound (issue 1183, AC3, AC4, AC5)

internal/link/watched.go

@@ -21,8 +21,7 @@ import (
 //
 // **In memory, on purpose.** A heartbeat is the least valuable message the mesh sends — the next one
 // is a minute away — and what a watchdog needs of it is the newest moment and the interval it said.
-// A machine's last word is kept in the store as well (`last_seen`), which is what S1 reads; these are
-// what the store does not keep: the interval, the node tools' word, and when the event loop last took
+// What the store does not keep: the node tools' word and its interval, and when the event loop last took
 // a message.
 
 // Beat is one emitter's newest heartbeat.
@@ -43,11 +42,9 @@ type Beats struct {
 // NewBeats is an empty record, started now.
 func NewBeats() *Beats { return &Beats{started: time.Now(), heard: map[string]Beat{}} }
 
-// HostBeats are the node-engines' heartbeats (S1); ToolsBeats the node tools' (S11).
-var (
-	HostBeats  = NewBeats()
-	ToolsBeats = NewBeats()
-)
+// ToolsBeats are the node tools' heartbeats (S11). The node-engine's alive message is not heard: a machine's last word is
+// the watchman's presence (novox/hq ADR 0433 §3).
+var ToolsBeats = NewBeats()
 
 // Heard records one heartbeat.
 func (b *Beats) Heard(node string, at time.Time, every time.Duration, version string) {