i18n: publish the glossary as a machine-readable term list

[sliptonic]

What to build

Under the client-owned-i18n model, each client maintainer translates their own UI — but "Inbox", "bind", "catalog", "set" must not fragment across languages. The core already holds the canonical vocabulary (docs/UBIQUITOUS_LANGUAGE.md); make it consumable: export the ratified terms as a structured artifact (JSON/YAML, committed in-repo and/or served) that client maintainers key their translation tables off.

The presets design already proved this pattern in-domain — (origin, label) identity with clients promoting their own translations. This applies the same idea to UI vocabulary.

Keep it thin: term slug, canonical English term, one-line definition, and a stable ID clients reference. No translations live in the core — those belong to clients.

Acceptance criteria

• Machine-readable term list generated from or reconciled with UBIQUITOUS_LANGUAGE.md
• Consumption path documented in HOWTO_BUILD_A_CLIENT.md
• Drift guard: a check (test or CI) that the export and the glossary doc stay in sync

Blocked by

None - can start immediately