feat(client): stub ClntObjMgrGetMapID

src/client/ObjMgr.cpp

@@ -0,0 +1,6 @@
+#include "client/ObjMgr.hpp"
+
+uint32_t ClntObjMgrGetMapID() {
+    // TODO
+    return -1;
+}

src/client/ObjMgr.hpp

@@ -0,0 +1,8 @@
+#ifndef CLIENT_OBJ_MGR_HPP
+#define CLIENT_OBJ_MGR_HPP
+
+#include <cstdint>
+
+uint32_t ClntObjMgrGetMapID();
+
+#endif