feat: Introduce StacError and StacErrorWidget for enhanced error handling

packages/stac/lib/src/framework/stac.dart

@@ -3,6 +3,7 @@ import 'dart:convert';
 
 import 'package:dio/dio.dart';
 import 'package:flutter/material.dart';
+import 'package:stac/src/framework/stac_error.dart';
 import 'package:stac/src/framework/stac_service.dart';
 import 'package:stac/src/services/stac_cloud.dart';
 import 'package:stac_core/actions/network_request/stac_network_request.dart';
@@ -16,6 +17,25 @@ typedef ErrorWidgetBuilder = Widget Function(
 
 typedef LoadingWidgetBuilder = Widget Function(BuildContext context);
 
+/// Global parse-error widget builder for Stac.
+///
+/// Allows apps to provide a custom widget when parsing a Stac widget/action
+/// fails. The builder receives useful context like the widget/action type,
+/// original JSON and stack trace (when available).
+///
+/// Example:
+/// ```dart
+/// Stac.initialize(
+///   errorWidgetBuilder: (context, errorDetails) {
+///     return Text('Error in ${errorDetails.type}: ${errorDetails.error}');
+///   },
+/// );
+/// ```
+typedef StacErrorWidgetBuilder = Widget Function(
+  BuildContext context,
+  StacError errorDetails,
+);
+
 class Stac extends StatelessWidget {
   const Stac({
     super.key,
@@ -34,13 +54,19 @@ class Stac extends StatelessWidget {
     List<StacActionParser> actionParsers = const [],
     Dio? dio,
     bool override = false,
+    bool showErrorWidgets = true,
+    bool logStackTraces = true,
+    StacErrorWidgetBuilder? errorWidgetBuilder,
   }) async {
     return StacService.initialize(
       options: options,
       parsers: parsers,
       actionParsers: actionParsers,
       dio: dio,
       override: override,
+      showErrorWidgets: showErrorWidgets,
+      logStackTraces: logStackTraces,
+      errorWidgetBuilder: errorWidgetBuilder,
     );
   }