Adds a public set of rules for the External Maintainer role: who qualifies,
how nominations work, what permissions Maintainers gain, what's expected
of them, and how step-down works.
The Core Team's individual roster is intentionally not enumerated. What's
public is the rules everyone plays by.
- New file: MAINTAINERS.md (English authoritative version) + 5 locale variants
matching the existing CONTRIBUTING.md i18n surface (de, fr, ja-JP, pt-BR,
zh-CN). Non-EN/non-zh-CN variants are machine-translated drafts marked at
the top — native-speaker review is welcome via follow-up PRs.
- CONTRIBUTING.md (and its 5 locale variants): adds a short
Becoming a Maintainer section that points at MAINTAINERS.md, so the
rules live in one place and translation drift is bounded.
Decisions not in this PR (intentional):
- No internal Core Team roster.
- No internal observability dashboards.
- No nomination PR / public voting flow (Core-Team-consensus-driven for now;
to be revisited once External Maintainers exceed 5).
Co-authored-by: Joey Li <lijinwei@open-design.ai>
