fix: newline in agentctl plan

Author: leo-aa88

internal/cli/plan.go

@@ -90,7 +90,7 @@ func writePlanOutput(cmd *cobra.Command, env, dsn string, p *plan.Plan, g *Globa
 		if _, err := fmt.Fprintf(out, "Environment: %s\nState: %s\n\n", env, dsn); err != nil {
 			return err
 		}
-		_, err := fmt.Fprint(out, plan.FormatPlan(p))
+		_, err := fmt.Fprintf(out, "%s\n", plan.FormatPlan(p))
 		return err
 	}
 }

internal/cli/plan_test.go

@@ -53,6 +53,9 @@ func TestPlan_firstPlan_allCreates(t *testing.T) {
 	if !strings.Contains(s, "Plan: 3 to add, 0 to change, 0 to delete") {
 		t.Fatalf("summary missing in:\n%s", s)
 	}
+	if !strings.HasSuffix(s, "\n") {
+		t.Fatalf("expected trailing newline in:\n%s", s)
+	}
 	for _, line := range []string{"+ create Project/plan-fixture", "+ create Policy/default", "+ create Tool/helper"} {
 		if !strings.Contains(s, line) {
 			t.Fatalf("missing %q in:\n%s", line, s)