Build modules take asks only within their node's build hours

mesh-build-go, -node and -image declare build-hours (node=HH:MM-HH:MM in the node's local time,
empty = any hour) and hand it to the SDK puller (the operator, 2026-10-26: g14 builds only from
18:00 to 06:00); their SDK pin moves to mesh-sdk d00dac1, which has it.

modules/mesh-build-node/cmd/mesh-build-node/asks.go

@@ -50,8 +50,12 @@ func (m *Module) Puller(steps []StepTool, source buildstep.AskSource) *buildstep
 	var watch func(string, func(stdio.ProvisionChange) error) error
 	// And the CPU bounds it (issue 1806's follow-up): the configured capacity is an upper bound, the node's build slice
 	// gives floor(its quota's cores / the module's cores-per-step) at once, read live; a test judges by its own Capacity.
+	// And the node's build hours (the operator, 2026-10-26: g14 builds only from 18:00 to 06:00): outside them it takes
+	// nothing new.
 	var cores func() float64
+	var hours func() (*buildstep.BuildWindow, string)
 	if capacity == nil {
+		hours = buildstep.NodeBuildHours(m.Settings, m.Node, m.Say)
 		capacity = buildstep.NodeCapacity(m.Settings, buildstep.DefaultCapacities, m.Node, m.Say)
 		watch = buildstep.WatchConfigServed
 		cores = buildstep.NodeCoresPerStep(m.Settings, buildstep.DefaultCoresPerStep[delivery.AskNode], m.Say)
@@ -62,7 +66,7 @@ func (m *Module) Puller(steps []StepTool, source buildstep.AskSource) *buildstep
 		load = func(key string) ([]byte, error) { return m.ReadPauses.Get(key) }
 	}
 	return &buildstep.Puller{Source: source, Language: delivery.AskNode, Node: m.Node, Put: m.Steps, PausePut: m.Pauses, Load: load,
-		Capacity: capacity, WatchConfig: watch, CoresPerStep: cores, Logf: m.Say,
+		Capacity: capacity, WatchConfig: watch, CoresPerStep: cores, BuildHours: hours, Logf: m.Say,
 		Run: func(ctx context.Context, a delivery.StepAsk) (any, error) {
 			if err := m.Prepare(ctx); err != nil {
 				return nil, err

modules/mesh-build-node/cmd/mesh-build-node/asks_test.go

@@ -95,6 +95,13 @@ func TestManifestTakesTheBuildCapacity(t *testing.T) {
 	if got := buildstep.NodeCoresPerStep(moduleDir+"/files/settings.json", 0, nil)(); got != buildstep.DefaultCoresPerStep[delivery.AskNode] {
 		t.Errorf("the settings template holds cores-per-step %g", got)
 	}
+	// And the build hours (the operator, 2026-10-26): a setting of their own, empty by default (any hour), in the template.
+	if hours := string(doc.Config[buildstep.BuildHoursSetting].Default); hours != `""` {
+		t.Errorf("the build-hours default = %s, want empty", hours)
+	}
+	if w, fault := buildstep.NodeBuildHours(moduleDir+"/files/settings.json", "g14", t.Errorf)(); w != nil || fault != "" {
+		t.Errorf("the settings template holds build hours %v (%s)", w, fault)
+	}
 	var capacity string
 	_ = json.Unmarshal(doc.Config[buildstep.CapacitySetting].Default, &capacity)
 	if capacity != buildstep.DefaultCapacities {