Absolute expiry time of accessToken. null means the upstream provider
did not issue a finite expiry (e.g. GitHub OAuth Apps classic tokens).
Consumers MUST treat null as "do not attempt refresh; reuse until the
provider explicitly invalidates". Required (no undefined) so adapters
are forced to make an explicit decision per provider.
Expiry encoding: Date per A4 two-tier design — see UserSession
for rationale.
Absolute expiry time of
accessToken.nullmeans the upstream provider did not issue a finite expiry (e.g. GitHub OAuth Apps classic tokens). Consumers MUST treatnullas "do not attempt refresh; reuse until the provider explicitly invalidates". Required (noundefined) so adapters are forced to make an explicit decision per provider.Expiry encoding:
Dateper A4 two-tier design — see UserSession for rationale.