Does it have cracks? Have you actualy seen any? Yes they can be
fixed . A neighbor hearing popping isnt relavent as is you mentioning
jacking the house and putting a new foundation. Conctete companys are
very carefull in winter especialy, their liability is very great and
they use additives when necessary . And stop work when weather makes it
unsafe for product performance. Leaks are a separate issue that need
to be fixed , but a closed -sealed new unventilated house can have
extremely high humidity as with tight construction and no air
circulating causing alot of issues even mold and floor cupping. Talk
to your concrete co for pour parameters and your top building
inspector. Or hire an indepandant engineer.