Internal deterministic encoder for frozen Kernel metadata and hashes.

Ordinary maps require binary UTF-8 keys or valid public symbol-reference wrappers and are recursively sorted by their normalized key bytes. {:object, pairs} accepts the same key types, preserves an explicit key order for versioned projections, and rejects duplicate normalized keys before a map could erase them. Symbol-reference values are likewise encoded as their display strings. Arrays retain their input order and output contains no insignificant whitespace.