Must the wife's jewelry, which she acquired as gifts before marriage, be itemized and added to the money subject to zakat, and is zakat obligatory for past years in which its existence was not known?

Your zakat on your wealth is not related to your wife's gifts and jewelry. You must pay zakat on your wealth that has completed a lunar year (hawl) and reached the nisab (minimum threshold). As for your wife's jewelry, there is no zakat on it according to the majority of scholars if it is for adornment. And if zakat is obligatory on it, it is on your wife, not on you. She must pay its zakat for past years if it reached the nisab, unless you voluntarily pay it on her behalf after informing her.