feat: create source item widget

- Display source name and description
- Handle tap event with snackbar

Author: fulleni

lib/headlines-search/widgets/source_item_widget.dart

@@ -0,0 +1,31 @@
+import 'package:flutter/material.dart';
+import 'package:ht_shared/ht_shared.dart'; // Import Source model
+
+/// A simple widget to display a Source search result.
+class SourceItemWidget extends StatelessWidget {
+  const SourceItemWidget({required this.source, super.key});
+
+  final Source source;
+
+  @override
+  Widget build(BuildContext context) {
+    return ListTile(
+      title: Text(source.name),
+      subtitle: source.description != null
+          ? Text(
+              source.description!,
+              maxLines: 2,
+              overflow: TextOverflow.ellipsis,
+            )
+          : null,
+      // TODO(you): Implement onTap navigation if needed for sources
+      onTap: () {
+        // Example: Navigate to a page showing headlines from this source
+        // context.goNamed('someSourceFeedRoute', params: {'id': source.id});
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(content: Text('Tapped on source: ${source.name}')),
+        );
+      },
+    );
+  }
+}