feat(core+backend/X11): 实现窗口状态变更（最大化/最小化/全屏）

src/backend/x11/window.h

@@ -3,6 +3,7 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <string.h>
+#include <xcb/xcb.h>
 #include <xcb/xcb_icccm.h>
 #include <xcb/xproto.h>
 
@@ -89,6 +90,12 @@ void window_set_icccm_wm_state(
   xcb_window_t window,
   xcb_icccm_wm_state_t state
 );
+void window_set_net_wm_state(
+  backend_t *backend,
+  xcb_window_t window,
+  size_t count,
+  xcb_atom_t *atoms
+);
 
 void window_list_push(window_list_t *window_list, xcb_window_t window);
 void window_list_reset(window_list_t *window_list);