Take the catalogue's composition rules into the node-engine

ADR 0593 §7: the composer with its refusals leaves mesh-sdk, so mesh-sdk
carries no composition rule. The catalogue functions only the
node-engine's composition reaches (Resolve, Resolution's Compose,
Declaration, DataItems, LeftOut, Rules and the rest, the settings,
placeholder and template refusals, the rendering helpers) are copied
with their tests into internal/compose/resolution; a method of a
mesh-sdk shape becomes a function taking it first. The composition
calls its own copies, and the captured catalogue its tests read lives
here now, shared by mesh-compose's tests.

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL

internal/compose/resolution/schedule_test.go

@@ -0,0 +1,34 @@
+package resolution
+
+import (
+	"strings"
+	"testing"
+
+	mcat "git.novox.be/novox/mesh-sdk/go/catalogue"
+)
+
+func TestAScheduledContainerRendersWithTheCronField(t *testing.T) {
+	// The resolver carries `schedule` into the rendered host declaration untouched, exactly as it
+	// carries run-once — a container's keys are copied through, so the host receives the field as
+	// written.
+	digest := "@sha256:" + strings.Repeat("a", 64)
+	r := mcat.Resolution{Node: "laptop", Modules: []mcat.Manifest{{
+		Module: "kometa",
+		Resources: []map[string]any{
+			{"id": "sync", "type": "container", "name": "sync",
+				"image": "registry.example/runtime" + digest, "schedule": "0 3 * * *"},
+		},
+	}}}
+	out, err := Declaration(r, mcat.Rendering{})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sync := indexOfID(out, "kometa.sync")
+	if sync == -1 {
+		t.Fatal("the scheduled container was lost in rendering")
+	}
+	if got, _ := out[sync]["schedule"].(string); got != "0 3 * * *" {
+		t.Errorf("schedule did not reach the host declaration: %+v", out[sync])
+	}
+}