chore(prisma): ajoute minStayNights/maxStayNights/minCapacity/seasonalConstraints au modèle Carbet (oubli PR#30)

prisma/schema.prisma

@@ -118,6 +118,13 @@ model Carbet {
   // Détails d'accès route pour ROAD_AND_RIVER (GPS, distance, type de piste).
   roadAccessNote     String?
   capacity           Int
+  // Contraintes séjour (plugin min-stay). null = pas de contrainte.
+  minStayNights      Int?
+  maxStayNights      Int?
+  minCapacity        Int?
+  // Contraintes saisonnières (plugin seasonality). JSON libre, schéma type :
+  // { closedInLowWater: bool, closedSeasons: ["WET"|"DRY"|"LOW_WATER"][], note: string }
+  seasonalConstraints Json?
   status             CarbetStatus @default(DRAFT)
   lastBookedAt       DateTime?
   createdAt          DateTime     @default(now())