Alec Baldwin wants a police presence on all sets where guns are being used. The actor, who fatally shot “Rust” cinematographer Halyna Hutchins last month when he fired a gun mistakenly loaded with live bullets, made the public plea Monday as Hollywood scrambles to avoid another catastrophe. “Every film/TV set that uses guns, fake or otherwise, should have a police officer on set, hired by the production, to specifically monitor weapons safety,” he tweeted from his locked account. After the accidental shooting, which also injured director Joel Souza, both Dwayne Johnson and “The Rookie” showrun...