The county’s deputy zoning administrator approved a food truck for Stinson Beach last month, and more than 50 community members sent in letters to support it. Steve and Lovisa Rubin, longtime Stinson residents, have plans for a seven-day-a-week food truck located next to their bike shop, Fritz Bikes. The food would be prepared offsite and there would be only two employees at any time in an effort to meet the community need for more dining…