Review B2: the f32 clock wrapped hourly and every star's twinkle jumped at the
wrap. It now accumulates in f64 and wraps at 86400 s; the shader rounds each
twinkle rate to whole cycles per wrap, so the stars are seamless. The High
cloud detail drift still re-patterns once per 24 h (noted).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
