ExIcaoVds.Clocks.Fixed (ex_icao_vds v0.3.2)

Deterministic clock for tests. Provide :date and :datetime in opts.

ExIcaoVds.issue(data,
  clock: ExIcaoVds.Clocks.Fixed,
  clock_opts: [date: ~D[2026-04-28], datetime: ~U[2026-04-28 12:00:00Z]]
)