Fetches and caches EVE SSO's JSON Web Key Set. The set is reused for
cacheTtlMs; a kid missing from the cached set triggers one refetch.
Fetches start at most once per refetchCooldownMs whatever triggers them
(an unknown kid, an expired cache, a failed earlier fetch), and
concurrent fetches share one request. When a refetch fails, the last good
key set stays in use.
Share one instance across verifications; a fresh instance fetches the key
set on its first use.
Fetches and caches EVE SSO's JSON Web Key Set. The set is reused for
cacheTtlMs; akidmissing from the cached set triggers one refetch. Fetches start at most once perrefetchCooldownMswhatever triggers them (an unknownkid, an expired cache, a failed earlier fetch), and concurrent fetches share one request. When a refetch fails, the last good key set stays in use.Share one instance across verifications; a fresh instance fetches the key set on its first use.