examples: add <cstdlib> header to core_compress example

Grok Compression · Grok Compression · commit af9305194279 · 2026-03-03T23:29:14.000-05:00
diff --git a/examples/core/core_compress.cpp b/examples/core/core_compress.cpp
@@ -29,6 +29,7 @@ of three approaches for the destination:
 #include <cstdio>
 #include <cstring>
 #include <memory>
+#include <cstdlib>
 #include <inttypes.h>
 
 #include "grok.h"
