Could recurring dreams, especially those seen by several people and concerning a specific matter such as marrying a committed person, be signs from Allah that necessitate waiting?

Dreams may indicate that the young man will marry you, but they are not to be relied upon. If the young man is righteous and you desire to marry him, there is no harm in expressing your desire to him directly or through someone close to him. If he agrees, let him propose to you. It is advisable to facilitate marriage and initiate it for its blessings. The Messenger of Allah, peace and blessings be upon him, said: "Indeed, among the blessings of a woman is the ease of her betrothal, the ease of her dowry, and the ease of her womb." If marriage with him is not facilitated, Allah may provide you with someone better, and do not abandon marriage with someone else for the sake of a dream; for rulings are not built upon dreams.