UNIVERSITY CITY, Mo. (AP) — When the coronavirus pandemic first hit the U.S., sales of window coverings at Halcyon Shades quickly went dark. So the suburban St. Louis business did what hundreds of other small manufacturers did: It pivoted to make protective supplies, with help from an $870,000 government grant. But things haven’t worked out as planned. The company quit making face shields because it wasn’t profitable. It still hasn’t sold a single N95 mask because of struggles to get equipment, materials and regulatory approval. “So far, it has been a net drain of funds and resources and energy,” Halcyon...