Add a backdoor to every listening post and the fanny pack

[Angel]

Currently, there are maps that the listening post does not have the syndicate fanny pack, such item would help a lot if you're planning to run a gimmick you might not want a backpack, and just for overall better inventory management, the fanny pack also makes the agent card a much better item, and without it, lowers its value as an item. Also, a back door for all listening posts, like how atlas listening post has two entrances, could be extremely useful in case security is chasing you, or someone is camping the post to attack you, or you're running a gimmick using the post as your evil syndicate base, and might want to do an emergency escape or something, so having a backdoor as the default for every map would be nice.