Can Kiddush Levanah be recited on Shabbat or Yom Tov when the time is about to run out?

A source-based Torah discussion of a time-sensitive question about Kiddush Levanah when the final opportunity falls on Shabbat or Yom Tov. This discovery layer identifies the issue and its Torah context without presenting a practical ruling; the full Hebrew source and its review status remain controlling.