It might come as little comfort to people who live near Jamaica Plain's version of the Big Dig, but Mayor Marty Walsh suggests downloading a socially-driven traffic app to navigate around the Casey Arborway project. The city recently entered a data-sharing agreement with Waze, a traffic app owned by Google. During a roundtable with local press last week, Walsh offered this advice about the Casey project: "Try to avoid it." Melina Schuler of the Mayor's Office followed up on Monday with more details, saying the city's Traffic Management Center "will be closely monitoring traffic in the area and making traffic signal adjustments to help offset congestion during demolition and construction." While the massive effort is a Massachusetts Department of Transportation project, it takes place on city streets.