An infusion of $13 million from the state will speed up two slow-going but significant projects in Connecticut’s largest city — the overhaul of a crumbling East End ammunition manufacturing site and construction of a long-promised youth center for the North End. The state Bond Commission, chaired by Gov. Ned Lamont, is scheduled to meet Dec. 21 to vote on a new round of borrowing. Its agenda, released this week, includes $10 million to continue cleanup at the former Remington Arms plant, an East Side landmark but also symbol of Bridgeport’s long-gone glory days as a manufacturing hub. Across town, at Madison and North avenues, the city has already torn down the former North End Boys and Girls Club. That work started in 2018. Under the agreement, Wakeman is leasing the land from the city but will own the new club it is building and operating there. A big part of the delay has been raising the construction and initial operating funds, a price tag that grew from $15 million to the current $23 million.