shared: Clean up includes

Split out of #37344.

src/shared/daemon-util.h

@@ -1,11 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <stdbool.h>
+#include "sd-daemon.h" /* IWYU pragma: export */
 
-#include "sd-daemon.h"
-
-#include "macro.h"
+#include "forward.h"
 
 #define NOTIFY_READY_MESSAGE "READY=1\n" "STATUS=Processing requests..."
 #define NOTIFY_STOPPING_MESSAGE "STOPPING=1\n" "STATUS=Shutting down..."
@@ -17,7 +15,6 @@ static inline const char* notify_start(const char *start, const char *stop) {
         return stop;
 }
 
-/* This is intended to be used with _cleanup_ attribute. */
 static inline void notify_on_cleanup(const char **p) {
         if (*p)
                 (void) sd_notify(false, *p);