Send an approved settings layer by a walk at once, so the operator's Approve is the act that takes effect (issue 641, ADR 0344)

The warrant set the layer and left the push as a second act nobody took: the
operator approved a betterbird change on Telegram and nothing reached g14.
Now the warrant opens a settings walk: the machines the layer reaches, one at
a time, the module judged on each at its gate, its end told once through
plan-moved. The ask and the proposer's answer say so instead of naming push.

cmd/mesh-controller/proposals.go

@@ -18,8 +18,9 @@ package main
 // it beside the layer (`settings` says it back), and records the warrant in the hand-act log on the bus, where a
 // person's decisions are read; the router edits the ask on every channel to its outcome. No seat event of its
 // own: nothing consumes one, and the installer's first user list in the node-engine's repository names every
-// controller event, so one would cost a node-engine change for a fact without a reader. The push afterwards is a
-// separate act, as it is for a layer set at the terminal.
+// controller event, so one would cost a node-engine change for a fact without a reader. No push is left for
+// afterwards: the warrant that sets the layer opens the walk that sends it (novox/hq ADR 0344, settings_walk.go),
+// so the operator's one Approve is the act that makes the change take effect.
 //
 // **What the operator reads** is the module, the machine, each key with its exact new value and, for a changed
 // key, the value it replaces. A value that may not leave the mesh (an address, a path, a secret's shape: the
@@ -47,6 +48,7 @@ import (
 	"git.novox.be/novox/mesh-sdk/go/asks"
 
 	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
 	"github.com/novox/mesh-controller/internal/link"
 	"github.com/novox/mesh-controller/internal/outward"
 )
@@ -179,11 +181,7 @@ func (p settingsProposal) ask(id string, machines []string) (asks.Ask, map[strin
 			"this fingerprint, through the mesh MCP server (mesh-controller.settings, proposal " + id + ") or with " +
 			"mesh-cli settings proposals " + id + ".")
 	}
-	if p.Clear {
-		b.WriteString(" Approved, the layer is removed at once and the machine takes it at its next push.")
-	} else {
-		b.WriteString(" Approved, the layer is set at once and the machine takes it at its next push.")
-	}
+	b.WriteString(" " + p.onApprove())
 	q := asks.Ask{ID: id, Headline: headline, Explanation: b.String(), Who: asks.Operator,
 		Expires: p.At.Add(askApproveFor), OnExpiry: "the proposal is discarded; nothing changes",
 		About: p.about()}
@@ -192,9 +190,9 @@ func (p settingsProposal) ask(id string, machines []string) (asks.Ask, map[strin
 		binds, _ := asks.ActDigest(boundAct(act))
 		oid := optionID(act.Label)
 		options[oid] = i
-		does := "the settings are set; nothing is pushed yet"
+		does := "the settings are set and sent to " + p.reaches() + " at once, each machine judged"
 		if p.Clear {
-			does = "the layer is removed; nothing is pushed yet"
+			does = "the layer is removed and that is sent to " + p.reaches() + " at once, each machine judged"
 		}
 		if act.Arguments["answer"] == answerDecline {
 			does = "nothing changes; the proposal is discarded"
@@ -519,15 +517,28 @@ func (pr proposer) propose(ctx context.Context, in proposeInput) (string, error)
 		fingerprint(p.Digest))
 	fmt.Fprintf(&b, "  until %s nothing changes: the layer is set only on Approve, and discarded on Decline or at expiry\n",
 		q.Expires.Local().Format("2006-01-02 15:04"))
-	fmt.Fprintf(&b, "  `settings proposals %s` shows it whole; once approved, `push %s` sends it", id, pushWord(p.Node))
+	fmt.Fprintf(&b, "  `settings proposals %s` shows it whole; once approved, a walk sends it to %s at once, one machine at "+
+		"a time, each judged, and the operator is told when it has landed (novox/hq ADR 0344)", id, p.reaches())
 	return b.String(), nil
 }
 
-func pushWord(node string) string {
-	if node == "" {
-		return "--behind"
+// reaches is the machines an approved layer is sent to, in words: the one it names, or every machine running the
+// module.
+func (p settingsProposal) reaches() string {
+	if p.Node == "" {
+		return "every machine running " + p.Module
 	}
-	return node
+	return p.Node
+}
+
+// onApprove is what the ask says Approve does (novox/hq ADR 0344 §4): the one Approve sets the layer and sends it.
+func (p settingsProposal) onApprove() string {
+	what := "the layer is set"
+	if p.Clear {
+		what = "the layer is removed"
+	}
+	return fmt.Sprintf("Approved, %s and sent at once to %s, one machine at a time, each judged; you are told when it "+
+		"has landed. A module that reads its settings only when it starts takes them at its next start.", what, p.reaches())
 }
 
 func newProposalID() string {
@@ -788,6 +799,22 @@ func setLayerIn(open *stores) setOnWarrant {
 				changed = "nothing changed"
 			}
 		}
-		return changed + " (ask " + askID + ")", nil
+		// **And sends it** (novox/hq ADR 0344): the layer the operator approved is walked to the machines it reaches
+		// at once. A walk that cannot be opened is said as the act's failure — the layer is set and nothing sends it.
+		walked, err := openSettingsWalk(ctx, open, inventory.PlanSettings{Module: p.Module, Node: p.Node, Ask: askID,
+			Change: changed})
+		if err != nil {
+			return "", fmt.Errorf("%s (ask %s) is set, and the walk that sends it could not be opened: %v — `push %s` sends it",
+				changed, askID, err, pushTo(p.Node))
+		}
+		return changed + " (ask " + askID + "); " + walked, nil
 	}
 }
+
+// pushTo is the push that sends a layer by hand when its walk could not: the machine, or every one behind.
+func pushTo(node string) string {
+	if node == "" {
+		return "--behind"
+	}
+	return node
+}