feat: alphabet list, change Layout etc

lib/database/app_database.dart

@@ -30,6 +30,10 @@ class Products extends Table {
 
   IntColumn get lowStockThreshold => integer()();
 
+  /// Products like tap water that are never counted; their stock is ignored.
+  BoolColumn get infiniteStock =>
+      boolean().withDefault(const Constant(false))();
+
   IntColumn get priceInCents => integer()();
 
   TextColumn get imagePath => text().nullable()();
@@ -200,7 +204,7 @@ class AppDatabase extends _$AppDatabase {
   AppDatabase([QueryExecutor? executor]) : super(executor ?? _openConnection());
 
   @override
-  int get schemaVersion => 13;
+  int get schemaVersion => 14;
 
   @override
   MigrationStrategy get migration {
@@ -295,6 +299,10 @@ class AppDatabase extends _$AppDatabase {
           await _backfillPurchaseRows();
           await _deleteOrphanedPurchaseRows();
         }
+
+        if (from < 14 && !await hasTableColumn('products', 'infinite_stock')) {
+          await migrator.addColumn(products, products.infiniteStock);
+        }
       },
     );
   }