What is the ruling on someone who swore by the Qur’an, intending beforehand not to harm anyone, then denied an incident that occurred, and their answer was neutral?

Lying is forbidden except in cases of necessity, if the intended purpose cannot be achieved otherwise. So, if a Muslim hides from an oppressor, it is obligatory to lie to conceal them. It is also commendable to use tawriyah (deliberately ambiguous speech) to avoid outright lying.