^^ i was going to mention that as well. the test where you hold the front brake and rock the bike forward and back would also show if that was the case.

if he swapped the front wheel and it still clunked, it probably wouldn't be pinging spokes.

and as yahnming said, this is almost definitely not an issue with your frame but is an issue with the hardware and/or installation of the hardware. you said you tightened the brakes so that could have been it. good luck and let us know what happens.