Say the heartbeat's interval, export the host's validator, grant the genesis controller Phase 1 (hq to-be 45)

The controller's watchdog of a machine's heartbeat (S1) is bound to three
of its intervals, and a bound the controller guessed would not move when
the interval does: the heartbeat now carries interval_seconds.

Its self-check (D1) must judge every composed declaration as the host
does, and a second validator written from the host's rules would drift
from them: the host's own parsing is exported, unchanged, as
github.com/novox/mesh-host/validate.

The installer's first user list grants what the controller now composes
for itself: its condition buckets, the condition and doctor-heartbeat
events, the bus's two consumer advisories and $SRV.INFO — or the first
controller would be refused them until the broker's machine is pushed.

internal/link/messages.go

@@ -28,6 +28,10 @@ const (
 // look like a stale one.
 type Alive struct {
 	Node string `json:"node"`
+	// IntervalSeconds is how often this node says it is there (novox/hq to-be 45 §3, S1): the
+	// controller's watchdog is bound to three of them, so the bound moves with the interval rather
+	// than with a number the controller guessed. A controller older than that ignores it.
+	IntervalSeconds int `json:"interval_seconds"`
 }
 
 // Signed is a declaration and the signature over it.

internal/link/run.go

@@ -514,7 +514,7 @@ func publishReport(ctx context.Context, bus Bus, m Membership, report Report,
 // publishAlive says this node is here, and nothing else.
 func publishAlive(ctx context.Context, bus Bus, m Membership, say Announce,
 	timeout time.Duration) {
-	body, err := json.Marshal(Alive{Node: m.Node})
+	body, err := json.Marshal(Alive{Node: m.Node, IntervalSeconds: int(AliveEvery / time.Second)})
 	if err != nil {
 		return
 	}