Place pluots, honey, 4 teaspoons vinegar, 1 tablespoon lemon juice, lemon peel, rosemary, coarse salt, and a pinch of pepper in a small saucepan. Bring to a boil over medium-high heat, stirring. Reduce heat to medium-low. Simmer until fruit has broken down and mixture is thick, stirring occasionally, about 20 minutes. Cool. Adjust seasonings, add chives.