feat: screenshot app improvement, WIndow Server supports full-screen overlay, Disks app UI improvements

template/sysroot/include/montauk/syscall.h

@@ -436,5 +436,8 @@ namespace montauk {
     inline int win_setcursor(int id, int cursor) {
         return (int)syscall2(Montauk::SYS_WINSETCURSOR, (uint64_t)id, (uint64_t)cursor);
     }
+    inline int win_setflags(int id, uint32_t flags) {
+        return (int)syscall2(Montauk::SYS_WINSETFLAGS, (uint64_t)id, (uint64_t)flags);
+    }
 
 }