perf(add_category): autoselect category type based on transaction type (#402)

* perf(add_category): autoselect category type based on transaction type

When creating a new category, the category type dropdown is preselected
based on the transaction type (income or expense).

- Import transaction provider in add_category
- Read transaction type using the transaction provider
- Default category type using transactionToCategoryProvider, or set to 'expense' if null
- Remove redundant "hide income" logic in initial setup

Ref: #390

* Remove unuseful comments

* Fix dart format

Author: gioisco

lib/pages/categories/add_category.dart

@@ -4,6 +4,7 @@ import '../../constants/constants.dart';
 import '../../constants/style.dart';
 import '../../model/category_transaction.dart';
 import '../../providers/categories_provider.dart';
+import '../../providers/transactions_provider.dart';
 import '../../ui/device.dart';
 import '../../ui/extensions.dart';
 
@@ -18,25 +19,27 @@ class AddCategory extends ConsumerStatefulWidget {
 
 class _AddCategoryState extends ConsumerState<AddCategory> {
   final TextEditingController nameController = TextEditingController();
-  CategoryTransactionType categoryType = CategoryTransactionType.income;
+  late CategoryTransactionType categoryType;
   String categoryIcon = iconList.keys.first;
   int categoryColor = 0;
 
   bool showCategoryIcons = false;
 
   @override
   void initState() {
-    if (widget.hideIncome) {
-      categoryType = CategoryTransactionType.expense;
-    }
+    super.initState();
+
+    final transactionType = ref.read(transactionTypeProvider);
+    categoryType = ref.read(transactionToCategoryProvider(transactionType)) ??
+        CategoryTransactionType.expense;
+
     final selectedCategory = ref.read(selectedCategoryProvider);
     if (selectedCategory != null) {
       nameController.text = selectedCategory.name;
       categoryType = selectedCategory.type;
       categoryIcon = selectedCategory.symbol;
       categoryColor = selectedCategory.color;
     }
-    super.initState();
   }
 
   @override