Initial commit: Brother QL USB-to-Network Bridge

- TCP server exposing USB Brother QL printers on port 9100
- Supports all Brother QL series label printers
- Async architecture for handling concurrent print jobs
- Raspberry Pi deployment script and systemd service
- Documentation for setup and InvenTree integration

config.py

@@ -0,0 +1,15 @@
+"""Configuration for Brother QL Bridge."""
+
+# TCP server settings
+TCP_HOST = "0.0.0.0"  # Listen on all interfaces
+TCP_PORT = 9100       # Standard raw printing port
+
+# USB printer settings
+# Set to None for auto-detection, or specify like "usb://0x04f9:0x2028"
+USB_DEVICE = None
+
+# Printer model (used for brother_ql compatibility)
+PRINTER_MODEL = "QL-570"
+
+# Logging
+LOG_LEVEL = "INFO"