The highest-ever Covid-19 case counts were reported in Marin over the past two weeks, signaling more trouble is on the way for local hospitals—even before Christmastime transmission has been detected. The stress on Marin’s hospitals lessened this week, but the dip in admissions is likely short-term. On Tuesday, 24 patients with Covid-19 were hospitalized, down from a peak of 35 two weeks ago, while 26 of 29 beds in intensive care units were occupied, an…