Expand description
Hex codec for the guest/host wire boundary.
Every loader that hands raw bytes across an untrusted boundary (Extism’s
JSON host-fn wire, Rhai’s script boundary) needs the same lowercase-hex
encode/decode pair. They were implemented independently and byte-identically
in uni-plugin-extism and uni-plugin-rhai; they live here so the
panic-safety property below is stated and tested once.