Add arena debug visualization tool

benchmarks/bench_parser_comparison.cpp

@@ -242,7 +242,7 @@ int main() {
                           .minEpochIterations(200);
 
   memory_bench.run("WeaselDB Parser (arena allocation)", [&] {
-    CommitRequest request(4096); // 4KB arena
+    CommitRequest request;
     std::string mutable_json = COMPLEX_JSON;
     bool result = request.parse_json(mutable_json.data(), mutable_json.size());
     ankerl::nanobench::doNotOptimizeAway(result);