The typological pattern of Ruth is: Naomi, the Jewish widow, is bereft; the Gentile daughter Ruth joins her; Naomi gets a savior when Boaz attaches himself to Ruth . That is, the pattern is not “Savior, then incorporation of Gentiles” but “incorporation of Gentiles, then Savior.”
In the fulfillment, it’s both. Jesus comes to bring the Gentiles into full sonship and holiness. But the Ruth pattern is also at work on the larger scale: The incorporation of the Gentile bride in the restoration period is preparation for the coming of the kinsman redeemer. Might we say that the kinsman redeemer comes to save the widow Israel precisely because of the pleas of the Gentiles? Might we say that the Redeemer comes to save the widow Israel because of His attraction to the Gentile daughter?