tree-wide: use forward declarations for wlr types

src/ssd/ssd-button.c

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
 #include <assert.h>
+#include <wlr/types/wlr_scene.h>
 #include "config/rcxml.h"
 #include "common/list.h"
 #include "common/mem.h"

src/ssd/ssd-titlebar.c

@@ -4,6 +4,7 @@
 #include <assert.h>
 #include <string.h>
 #include <wlr/render/pixman.h>
+#include <wlr/types/wlr_scene.h>
 #include "buffer.h"
 #include "common/mem.h"
 #include "common/string-helpers.h"

src/ssd/ssd.c

@@ -9,6 +9,7 @@
 #include "ssd.h"
 #include <assert.h>
 #include <strings.h>
+#include <wlr/types/wlr_cursor.h>
 #include <wlr/types/wlr_scene.h>
 #include "common/mem.h"
 #include "config/rcxml.h"