fix(admin): explicit compare fn on CampaignProgressionTable day sort

Sonar flagged the plain `.sort()` as a reliability issue (implementation-
defined ordering). Mirror the chart's compare pattern with `localeCompare`
to match.

Author: LucasCharrier

packages/app/src/modules/admin/stats/CampaignProgressionTable.tsx

@@ -20,7 +20,7 @@ export function CampaignProgressionTable({ series }: Props) {
 		new Set(
 			series.flatMap(({ points }) => points.map(({ day }) => day.slice(5))),
 		),
-	).sort();
+	).sort((a, b) => a.localeCompare(b));
 
 	const byDayByYear = new Map<number, Map<string, number>>();
 	for (const { year, points } of series) {