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/widgets/debug_frame_viewer.dart

@@ -10,6 +10,14 @@ class DebugFrameViewer {
     Uint8List frame,
     String title,
   ) {
+    // Helper to read uint32 little-endian
+    int readUint32LE(Uint8List data, int offset) {
+      return data[offset] |
+          (data[offset + 1] << 8) |
+          (data[offset + 2] << 16) |
+          (data[offset + 3] << 24);
+    }
+
     final hexString = frame
         .map((b) => b.toRadixString(16).padLeft(2, '0'))
         .join(' ');