The legislative authority of the government of this city, except as otherwise specifically provided in the charter, shall be vested in a governing body to be composed of a mayor and five councilmembers. The governing body established shall in all respects be a successor to and continuation of the governing authority under prior law. The mayor and councilmembers shall be elected in the manner provided by general law and this charter. The mayor and members of the council shall serve for terms of four years and until their respective successors are elected and qualified. No person shall be eligible to serve as mayor or councilmember unless that person shall have been a resident of the city for 12 months prior to the date of election of mayor or members of the council; the mayor and each councilmember shall continue to reside therein during that member's period of service and to be registered and qualified to vote in municipal elections of this city.