fix(ui): reuse shared file path picker for script settings (#1496)

ui/flutter/lib/features/settings/presentation/pages/settings_page.dart

@@ -1,6 +1,5 @@
 import 'dart:async';
 
-import 'package:file_picker/file_picker.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart' show Divider, Icons, Scrollbar, ScrollbarOrientation;
 import 'package:flutter/widgets.dart';
@@ -1376,12 +1375,7 @@ class _SettingsPageState extends ConsumerState<SettingsPage> {
       title: index == null ? context.l10n.addScript : context.l10n.editScript,
       fieldLabel: context.l10n.scriptPath,
       initialValue: index == null ? '' : paths[index],
-      pickPath: Util.isDesktop()
-          ? () async {
-              final file = await FilePicker.pickFile();
-              return file?.path;
-            }
-          : null,
+      pickFile: true,
     );
     if (value == null || !mounted) return;
     _mutateConfig((config) {

ui/flutter/lib/features/settings/presentation/widgets/settings_list_editor.dart

@@ -122,7 +122,7 @@ Future<String?> showTextSettingDialog(
   required String fieldLabel,
   String initialValue = '',
   bool requireHttpUrl = false,
-  Future<String?> Function()? pickPath,
+  bool pickFile = false,
   Future<void> Function(String value)? onTest,
 }) async {
   final controller = TextEditingController(text: initialValue);
@@ -189,16 +189,12 @@ Future<String?> showTextSettingDialog(
               children: [
                 Text(fieldLabel, style: TextStyle(color: palette.textSecondary, fontSize: 12)),
                 const SizedBox(height: 6),
-                if (pickPath == null)
+                if (!pickFile)
                   AppTextField(controller: controller)
                 else
-                  AppPathPickerField(
+                  AppPathPickerField.file(
                     controller: controller,
                     desktopWidth: AppDesignTokens.settingsFormControlWidth,
-                    onPick: () async {
-                      final path = await pickPath();
-                      if (path != null && path.isNotEmpty) controller.text = path;
-                    },
                   ),
                 if (validationMessage != null || testMessage != null) ...[
                   const SizedBox(height: 8),