Quarterback J.P. Losman, the heir apparent to Drew Bledsoe’s starting job in Buffalo, reached contract agreement with the Bills on Saturday, fulfilling the charge of the former Tulane star to his agent to complete a deal that would get him into camp on time. Losman was the second of the Bills’ two choices in the first round of the 2004 draft, and Buffalo had to trade up into Dallas’ spot at No. 22, sacrificing their first-round pick in ’05, to get him. Buffalo chose wide receiver Lee Evans, who is still unsigned, with their own pick in the first round, the 13th overall selection. General manager Tom Donahoe, who remains unafraid to make bold moves even in the face of occasional criticism, obviously feels Losman represents the team’s future. The contract is for five years and has a base value of $7.7 million, with $5.586 million of that in guarantees, largely an initial signing bonus and two option bonuses. The contract can top out, with escalators, at $24.58 million