[GR-58622] Compact binary encoding for ObjectCopier.

[graalvmbot]

A binary encoding for ObjectCopier that uses string deduplication and frequency encoding together with variable-length integers. This brings down the output size for layer-snapshot-graphs-libjavabaselayer by ~75%, and common compression algorithms reduce it by another 60-80%, resulting in a total reduction by 90%-95% compared to the current string encoding. Part of that is achieved by omitting the count, names and types of object fields and names of enum constants, and instead including 16-bit fingerprints to detect when types are different between decoding and encoding.