feat: Enhance MeshCoreConnector with storage metrics and improve error handling

- Added storageUsedKb and storageTotalKb properties to MeshCoreConnector.
- Updated battery and storage frame parsing with improved error handling.
- Refactored log RX data handling to use BufferReader for better readability and error management.
- Enhanced message parsing in ChannelMessage and Message classes to utilize BufferReader.
- Introduced new text type for signed messages in meshcore_protocol.dart.
- Updated BLE debug log screen to use BufferReader for payload parsing.
- Refactored message retry service to handle ACK hashes as integers instead of Uint8List.
- Improved message storage serialization and deserialization to accommodate new expectedAckHash type.
- Added wasPulled property to Contact model for better state management.

lib/models/contact.dart

@@ -18,6 +18,7 @@ class Contact {
   final DateTime lastSeen;
   final DateTime lastMessageAt;
   final bool isActive;
+  final bool wasPulled;
   final Uint8List? rawPacket;
 
   Contact({
@@ -34,6 +35,7 @@ class Contact {
     required this.lastSeen,
     DateTime? lastMessageAt,
     this.isActive = true,
+    this.wasPulled = false,
     this.rawPacket,
   }) : lastMessageAt = lastMessageAt ?? lastSeen;