Bad news for thrifty fashionistas: Filene’s Basement Inc. is filing for Chapter 11 bankruptcy protection and selling 17 of its 25 stores for $22 million. But not all is lost. The sold stores, including the flagship location in Boston, will still be operated under Filene’s name and sell designer goods at lower prices. The rest of Filene’s assets will go up for auction in five weeks. A few months ago the chain closed 11 of its stores, noting that its foray into the suburbs was ill-timed as consumers slashed their spending amid the recession.