ALLENTOWN — The other day a dozen people crowded around a ring of tables in a Macungie church community room, one of those mostly featureless spaces crowded with beige folding chairs where, so often, the call of faith turns quietly and efficiently into action. The group is the core of Family Promise of Lehigh County, a fledgling chapter of a national organization that unites denominations in an ecumenical charge against what is known as conditional homelessness — the kind that afflicts people who find themselves out of work and broke, living an unhappy nomadic existence in cars or bouncing among the cheapest and seediest motels. In 2016, there were nearly 550,000 homeless people in the United States, including nearly 16,000 in Pennsylvania, according to the federal Department of Housing and Urban Development.