NEW ORLEANS — From the outside, the abandoned Family Dollar store in the Lower 9th Ward looks intimidating. It’s covered in graffiti, with aluminum cans and trash dotting the parking lot. It sits on a street with other empty lots and decayed buildings — symbols of the lasting devastation this neighborhood, one of the city’s poorest, has endured since Hurricane Katrina. But inside, the store is a welcoming oasis. Twinkly string lights adorn racks of donated clothing. Shelves and bins overflow with children’s books, allergy medications, and toiletries. Curtains cordon off one side of the room, where there’s a stage for musicians and a neon sign depicting roller skates for weekly free skate nights. The space is part free thrift store, part over-the-counter pharmacy, part punk show venue — and wholly “a radical community center,” said Dan Bingler, who runs the place.