Star Wars: The Clone Wars (2008) ends with Ziro the Hutt exposed and arrested, Jabba the Hutt signing a treaty that gives the Republic passage through Hutt space, and Ahsoka Tano staying on as Anakin Skywalker's partner. Jabba recognizes that the Jedi saved his son rather than stole him, and the treaty is a major strategic win in a war fought over trade routes and space lanes.
Why does that matter? Because the whole kidnapping was built to push the Hutts toward the Separatists. Count Dooku's scheme fails, though the Separatists remain a threat, so the film closes the Rotta plot without ending the war.
The structure of the final stretch is worth reading closely. After the forced landing near Jabba's palace, the two leads are split: Anakin faces Dooku in a duel while Ahsoka carries the sick Rotta onward. Jabba first wants the Jedi punished because he believes they are behind the kidnapping. Padmé Amidala then exposes Ziro's betrayal. In that order of events, the Jedi are cleared by an investigation and not by winning a fight, and the duel with Dooku only buys time for the delivery.
The personal ending is quieter. Ahsoka earns Anakin's respect, and the two become an established team. That pairing is what sets up the continuing Clone Wars television series.
Comparison with the neighboring films: Star Wars: Episode II - Attack of the Clones is Episode II and Star Wars: Episode III - Revenge of the Sith is Episode III, and this spinoff sits between them in chronological order. Star Wars: Episode I - The Phantom Menace is first in that order, so by the time of this film two main saga films have already set the war up. Where a numbered episode closes on a turning point for the whole galaxy, this film closes on a treaty and a partnership, and it says plainly that the Separatists remain a threat.
Opinion: writer Priya Nair argues the film works better as a setup for Anakin and Ahsoka than as a standalone story, because the Rotta chase is simple and the treaty is the real payoff.