Democratic Assemblywoman Mary Hayashi of Castro Valley has been charged with felony grand theft after being caught on video surveillance allegedly shoplifting more than $2,000 worth of merchandise from San Francisco’s Neiman Marcus store on Union Square, prosecutors say. Hayashi, 45, who has served in the Assembly since 2006 — and is married to Alameda Superior Court Judge Dennis Hayashi — was arraigned Thursday in San Francisco Superior Court. She had earlier posted $15,000 bail.