Anaheim Police Department’s award-winning Mounted Enforcement Unit stands calm against a wave of stimuli on a recent day at Huntington Beach. Officers walk up to the horses while holding surfboards and portable speakers, waves crash on the shore, people shout greetings as they whiz past on bicycles, and beach umbrellas and tents are propped up in the sand nearby. Any of these elements could spook a horse, but the officers and their horses remain steadfast, largely due to extensive training and practice. “There is no such thing as a bombproof horse,” said Anaheim Officer Eric Anderson, who is also president…