internal: replace INT_MAX with WORKSPACE_INVALID

src/macros.hpp

@@ -22,6 +22,8 @@
 
 #define STRVAL_EMPTY "[[EMPTY]]"
 
+#define WORKSPACE_INVALID -1L
+
 #define LISTENER(name)                                                                                                                                                             \
     void               listener_##name(wl_listener*, void*);                                                                                                                       \
     inline wl_listener listen_##name = {.notify = listener_##name}