**Added multi-interface support (TCP, USB, Bluetooth)**
This update extends the Meshtastic client with full connectivity options:
* **TCPInterface** for network connections (default)
* **SerialInterface** for USB or serial devices (auto-detect supported)
* **BLEInterface** for Bluetooth Low Energy devices (via `bleak`)
Users can now choose their preferred connection type directly from the **Connection** menu.
Requires: `pip install meshtastic bleak pyserial`
