Trying to do the notification for all users.

lib/models/activity.dart

@@ -21,6 +21,7 @@ class Activity {
   final DateTime createdAt;
   final DateTime updatedAt;
   final DateTime? date; // Date prévue pour l'activité
+  final String? createdBy; // ID de l'utilisateur qui a créé l'activité
 
   Activity({
     required this.id,
@@ -42,6 +43,7 @@ class Activity {
     required this.createdAt,
     required this.updatedAt,
     this.date,
+    this.createdBy,
   });
 
   /// Calcule le score total des votes
@@ -108,6 +110,7 @@ class Activity {
     DateTime? updatedAt,
     DateTime? date,
     bool clearDate = false,
+    String? createdBy,
   }) {
     return Activity(
       id: id ?? this.id,
@@ -129,6 +132,7 @@ class Activity {
       createdAt: createdAt ?? this.createdAt,
       updatedAt: updatedAt ?? this.updatedAt,
       date: clearDate ? null : (date ?? this.date),
+      createdBy: createdBy ?? this.createdBy,
     );
   }
 
@@ -154,6 +158,7 @@ class Activity {
       'createdAt': Timestamp.fromDate(createdAt),
       'updatedAt': Timestamp.fromDate(updatedAt),
       'date': date != null ? Timestamp.fromDate(date!) : null,
+      'createdBy': createdBy,
     };
   }
 
@@ -179,6 +184,7 @@ class Activity {
       createdAt: (map['createdAt'] as Timestamp).toDate(),
       updatedAt: (map['updatedAt'] as Timestamp).toDate(),
       date: map['date'] != null ? (map['date'] as Timestamp).toDate() : null,
+      createdBy: map['createdBy'],
     );
   }