fix(setup): the workload-ns SMTP mirror must carry the target namespace

'smtpSecretManifest' hardcoded namespace=felis, so the 'configure email'
refresh of the minecraft-namespace copies failed before it began: kubectl
refuses a manifest whose namespace conflicts with -n (found live: 'the
namespace from the provided object "felis" does not match the namespace
"minecraft"'), and the felis-config mirror never ran at all because the
smtp apply returned early. A later SMTP change could therefore never reach
the reaper's pre-reap warnings — the exact failure the refresh was added to
close.

Render the Secret with the caller's namespace (felis for the control-plane
apply, the workload namespace for the mirror). Regression test pins both.

cmd/felis/tui_smtp_test.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"sigs.k8s.io/yaml"
+)
+
+// TestSMTPSecretManifestCarriesTargetNamespace pins the fix for the
+// workload-namespace replica: kubectl refuses a manifest whose namespace
+// conflicts with -n ("the namespace from the provided object ... does not
+// match"), so the mirror must render felis-smtp with the TARGET namespace —
+// otherwise the "configure email" refresh fails on the first apply and the
+// felis-config mirror never runs at all.
+func TestSMTPSecretManifestCarriesTargetNamespace(t *testing.T) {
+	for _, ns := range []string{"felis", "minecraft"} {
+		b, err := smtpSecretManifest("pw", ns)
+		if err != nil {
+			t.Fatalf("render for %s: %v", ns, err)
+		}
+		var got struct {
+			Metadata struct {
+				Namespace string `json:"namespace"`
+			} `json:"metadata"`
+		}
+		if err := yaml.Unmarshal(b, &got); err != nil {
+			t.Fatalf("unmarshal for %s: %v", ns, err)
+		}
+		if got.Metadata.Namespace != ns {
+			t.Fatalf("manifest namespace = %q, want %q", got.Metadata.Namespace, ns)
+		}
+		if !strings.Contains(string(b), "name: felis-smtp") {
+			t.Fatalf("manifest must still name felis-smtp: %s", b)
+		}
+	}
+}