Default filters (#755)

* Bug fix for filters

- Fix key shadowing

* Adjust default filters for stock list

* Adjust default filter values

* Add "active" filter for stock items

* Code formatting

* Add "default ordering" option

* Enable pathstring sorting

* dart format

lib/widget/paginator.dart

@@ -42,6 +42,9 @@ abstract class PaginatedSearchState<T extends PaginatedSearchWidget>
   // Override in implementing class
   String get prefix => "prefix_";
 
+  // Default ordering option (can be overridden)
+  String get defaultOrdering => "";
+
   // Should be overridden by an implementing subclass
   Map<String, Map<String, dynamic>> get filterOptions => {};
 
@@ -103,6 +106,9 @@ abstract class PaginatedSearchState<T extends PaginatedSearchWidget>
     if (field != null && orderingOptions.containsKey(field.toString())) {
       // A valid ordering field has been found
       return field.toString();
+    } else if (defaultOrdering.isNotEmpty) {
+      // A default ordering value is supplied
+      return defaultOrdering;
     } else if (orderingOptions.isNotEmpty) {
       // By default, return the first specified key
       return orderingOptions.keys.first;

lib/widget/part/category_list.dart

@@ -61,9 +61,16 @@ class _PaginatedPartCategoryListState
     },
   };
 
+  @override
+  String get defaultOrdering => "pathstring";
+
   @override
   Map<String, String> get orderingOptions {
-    Map<String, String> options = {"name": L10().name, "level": L10().level};
+    Map<String, String> options = {
+      "name": L10().name,
+      "pathstring": L10().path,
+      "level": L10().level,
+    };
 
     // Note: API v69 changed 'parts' to 'part_count'
     if (InvenTreeAPI().apiVersion >= 69) {

lib/widget/stock/location_list.dart

@@ -52,10 +52,14 @@ class _PaginatedStockLocationListState
   @override
   Map<String, String> get orderingOptions => {
     "name": L10().name,
+    "pathstring": L10().path,
     "items": L10().stockItems,
     "level": L10().level,
   };
 
+  @override
+  String get defaultOrdering => "pathstring";
+
   @override
   Map<String, Map<String, dynamic>> get filterOptions => {
     "cascade": {