Refactor Cayenne LPP parsing with error handling and logging

- Added error handling and logging to the Cayenne LPP parsing methods to manage malformed data gracefully.
- Improved the structure of the parsing logic for better readability and maintainability.
- Updated the Contact model to include error handling during frame parsing.
- Refactored Channels, Contacts, Map, and Neighbours screens to utilize a new AppBarTitle widget for consistent app bar design.
- Enhanced the BatteryIndicator widget to display SNR information for direct repeaters.
- Introduced SNRUi class for better management of SNR icon and text representation.
- Improved error handling in PathTraceMap and Neighbours screens to log errors appropriately.

lib/widgets/app_bar.dart

@@ -0,0 +1,46 @@
+import 'package:flutter/material.dart';
+import 'package:meshcore_open/connector/meshcore_connector.dart';
+import 'package:meshcore_open/widgets/battery_indicator.dart';
+import 'package:provider/provider.dart';
+
+class AppBarTitle extends StatelessWidget {
+  final String title;
+  final TextStyle? style;
+  final Widget? leading;
+  final Widget? trailing;
+  const AppBarTitle(
+    this.title,
+    this.style, {
+    this.leading,
+    this.trailing,
+    super.key,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final connector = context.watch<MeshCoreConnector>();
+
+    return Row(
+      mainAxisAlignment: MainAxisAlignment.start,
+      children: [
+        Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            if (leading != null) leading!,
+            Text(title),
+            if (connector.isConnected && connector.selfName != null)
+              Center(
+                child: Text(
+                  '(${connector.selfName})',
+                  style: TextStyle(fontSize: 14, color: Colors.grey[600]),
+                ),
+              ),
+          ],
+        ),
+        const SizedBox(width: 8),
+        BatteryIndicator(connector: connector),
+        if (trailing != null) trailing!,
+      ],
+    );
+  }
+}