Marin County Parks began a $99,000 restoration project on the Agate Beach Trail in Bolinas last week, part of an initiative to improve access to the county’s trail system. Beginning last week, the trailhead leading to Agate Beach is closed to the public from 7 a.m. to 5:30 p.m. on weekdays only. Construction, which is likely to last around a month, will include drainage improvements, resurfacing to level the pathway and the installation of box…