SACRAMENTO — California is poised to become the front line of America’s vaccination wars. State lawmakers are drafting the toughest covid-19 vaccine legislation in the country, backed by a new pro-vaccine lobbying force promising to counter anti-vaccine activists who have threatened government officials and shut down public meetings across the state. Legislators want to require most Californians to get the shots — not just schoolchildren and health care workers — and eliminate the exemptions that would allow many people to get out of them. But vaccine opponents say Democratic-led efforts to ad…