Client libraries in other languages

Section 9.1 of the specification welcomes contributed clients (Go, PowerShell, R, Lua, Julia are named) against the container format, and schedules none. The Python and JavaScript clients are held to one ranking by a committed golden container and query vector, so a new client has a ready contract test: read `tests/golden/`, run the same query, and match the ranking. A contributed client should ship with that test and a line on `docs/how-to/search-a-compendium.md`.

Start with Section 9.1 of the specification and inspect the existing Python and JavaScript clients, then read tests/golden/ to understand the committed container, query vector, and expected ranking. A contribution is done when a client for one of the named languages passes the same contract test and has a line added to docs/how-to/search-a-compendium.md.

Written by the indexing model from the issue text.