feat: Add library directive to multiple BLoC and service files for improved organization

lib/components/account/account_content.dart

@@ -18,6 +18,7 @@
 ///
 /// The component automatically loads account data when initialized and
 /// provides a clean interface for managing group-based expenses.
+library;
 import 'package:flutter/material.dart';
 import 'package:travel_mate/blocs/user/user_bloc.dart';
 import '../../models/account.dart';

lib/components/account/add_expense_dialog.dart

@@ -55,6 +55,7 @@
 /// - Expense
 /// - Group
 /// - ExpenseBloc
+library;
 import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';

lib/components/account/balances_tab.dart

@@ -3,6 +3,7 @@
 /// the amount they owe, and their overall balance status (to pay, to receive, or balanced).
 ///
 /// The widget handles both light and dark themes and provides a fallback UI for empty balance lists.
+library;
 
 import 'package:flutter/material.dart';
 import '../../models/user_balance.dart';

lib/components/account/expense_detail_dialog.dart

@@ -5,6 +5,7 @@
 /// The dialog is highly interactive and adapts its UI based on the current user's permissions and the state
 /// of the expense. It also integrates with BLoC for state management and supports features like receipt display
 /// and split payment marking.
+library;
 
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';