SAN FRANCISCO (AP).- The Solomon R. Guggenheim Museum in New York City. The Fallingwater home in southwestern Pennsylvania. But a child’s doghouse Frank Lloyd Wright designed hundreds of landmark buildings and homes during a prolific career that spanned more than seven decades. But in what is widely considered a first and only for the famed architect, Wright indulged a young boy’s humble request for a dog house in 1956 and sent him designs for the structure. “I was probably his youngest client and poorest client,” Jim Berger, now 68, said during a recent phone interview. Berger rebuilt the doghouse last year with his brother, using the original plans. It was featured in a documentary film and will be displayed during screenings starting this month. Wright designed Berger’s family’s home in the Marin County town of San Anselmo, prompting the then-12 years old Berger to ask his dad if Wright would design a home for his black Labrador, Eddie. Berger’s dad said he didn’t know, so Be