In the one mayoral candidate forum this year, Mayor Ed Lee didn't have to field many questions about his administration's assessment and goals for housing and economic development. But now we got the chance to ask about it. With a clear path toward toward re-election, Mayor Ed Lee's message about the future of residential and office growth in the city isn't exactly "stay the course." But he stresses that the planning and investment already under way will create more good than bad for San Francisco. Watch…