Store ordered list of memory frees.

server/TracyEvent.hpp

@@ -236,6 +236,7 @@ struct PlotData
 struct MemData
 {
     Vector<MemEvent> data;
+    Vector<uint64_t> frees;
     flat_hash_map<uint64_t, size_t, nohash<uint64_t>> active;
     uint64_t high = std::numeric_limits<uint64_t>::min();
     uint64_t low = std::numeric_limits<uint64_t>::max();