Data license

Everything under `facts/` (the registry of verified facts, in YAML) and the
generated fact pages is licensed under Creative Commons Attribution 4.0
International (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/

Attribution: "apifacts registry (CC BY 4.0)" with a link to the fact's
page or to the repository. Code is licensed separately under the MIT License
(see LICENSE). Decision 2026-10-17, docs/decisions.md.
