The city’s plan to convert Williamsburg’s Broadway Triangle area from a manufacturing-zoned site to a residential community won its first approval from Community Board 1′s land-use committee on Tuesday. The Department of Housing Preservation and Development’s controversial plan is to rezone the 31-acre portion of the triangle to create 1,851 units of housing, 905 of which would charge below-market rents. Supporters of the plan say the area needs affordable housing, while opponents allege corruption between the city and two neighborhood groups that have been awarded first dibs at affordable housing contracts. The city awarded the contracts to the United Jewish Organizations of Williamsburg and the Bushwick Ridgewood Senior Citizens Council, without putting the sites up for bid.