What is the ruling on taking a Qard Hasan (interest-free loan) from an American bank to invest it in my country, knowing that I can repay it within one year, and does the debt remain my responsibility to the bank if I die before repayment?

It is permissible to benefit from a loan if it is not conditioned on interest or late fees. If the debtor dies, their debt is paid from their estate. If they leave nothing behind, and the public treasury (Bayt al-Mal) is unavailable or corrupted, then if they intended to repay the debt, there is no blame on them, based on the hadith (definition): "Debts are two types: whoever dies intending to repay it, I am his guardian; and whoever dies not intending to repay it, that is the one from whose good deeds will be taken, and on that day there will be neither dinar nor dirham."