BELFAST, Maine — Ann Mullen — a slight, bespectacled octogenarian — was a familiar sight to lots of folks in Belfast, as she spent countless hours working to make the gardens at Post Office Square and Grove Cemetery a little more beautiful. Mullen, 85, died earlier this week of a chronic heart condition, shortly after surmounting COVID-19, according to her family. “Everybody knew her and saw her out there every single day, doing her thing,” her close friend and fellow gardener Carol Yee said.