feat: Add User and UserBalance models with serialization methods

feat: Implement BalanceRepository for group balance calculations

feat: Create ExpenseRepository for managing expenses

feat: Add services for handling expenses and storage operations

fix: Update import paths for models in repositories and services

refactor: Rename CountContent to AccountContent in HomePage

chore: Add StorageService for image upload and management

lib/blocs/expense/expense_event.dart

@@ -0,0 +1,87 @@
+import 'package:equatable/equatable.dart';
+import '../../models/expense.dart';
+import 'dart:io';
+
+abstract class ExpenseEvent extends Equatable {
+  const ExpenseEvent();
+
+  @override
+  List<Object?> get props => [];
+}
+
+class LoadExpensesByGroup extends ExpenseEvent {
+  final String groupId;
+
+  const LoadExpensesByGroup(this.groupId);
+
+  @override
+  List<Object?> get props => [groupId];
+}
+
+class CreateExpense extends ExpenseEvent {
+  final Expense expense;
+  final File? receiptImage;
+
+  const CreateExpense({
+    required this.expense,
+    this.receiptImage,
+  });
+
+  @override
+  List<Object?> get props => [expense, receiptImage];
+}
+
+class UpdateExpense extends ExpenseEvent {
+  final Expense expense;
+  final File? newReceiptImage;
+
+  const UpdateExpense({
+    required this.expense,
+    this.newReceiptImage,
+  });
+
+  @override
+  List<Object?> get props => [expense, newReceiptImage];
+}
+
+class DeleteExpense extends ExpenseEvent {
+  final String expenseId;
+
+  const DeleteExpense(this.expenseId);
+
+  @override
+  List<Object?> get props => [expenseId];
+}
+
+class MarkSplitAsPaid extends ExpenseEvent {
+  final String expenseId;
+  final String userId;
+
+  const MarkSplitAsPaid({
+    required this.expenseId,
+    required this.userId,
+  });
+
+  @override
+  List<Object?> get props => [expenseId, userId];
+}
+
+class ArchiveExpense extends ExpenseEvent {
+  final String expenseId;
+
+  const ArchiveExpense(this.expenseId);
+
+  @override
+  List<Object?> get props => [expenseId];
+}
+
+// Événement privé pour les mises à jour du stream
+class ExpensesUpdated extends ExpenseEvent {
+  final List<Expense> expenses;
+  final String? error;
+
+  const ExpensesUpdated(this.expenses, {this.error});
+
+  @override
+  List<Object?> get props => [expenses, error];
+}