Does the Qudsi Hadith: "O My servant, just as I have not demanded of you the deeds of tomorrow, do not demand of Me the provision of tomorrow," mean that we should not ask God to improve our circumstances, such as a better job or marriage?

The saying "The supplications of the prophets, peace be upon them, were all for matters of the Hereafter" is not a hadith; rather, it is from the Isra'iliyyat (Judaic traditions). Legal texts have indicated the permissibility of supplicating for the good of both this world and the Hereafter, as Allah Almighty says: "And among them is he who says, 'Our Lord, give us in this world [that which is] good and in the Hereafter [that which is] good and protect us from the punishment of the Fire.'" (Quran 2:201) The majority of the Prophet's supplications, peace be upon him, were also like this. The Prophet supplicated for Anas for abundance in wealth, children, and blessings.