Céline Dion fans participate in an open-air karaoke event in Paris, on Sept. 11, 2026. The diva from Quebec has long been an adored cultural figure in France, but Dion’s comeback tour, beginning with a 16-day residency in Paris, has seen such a fever of attention that Le Monde compared it to Beatlemania. (Dmitry Kostyukov/The New York Times) By CATHERINE PORTER and GIULIA IMBERT Paris hasn’t just opened its arms to Céline Dion. It has declared its fevered, undying love for her. After the…