Initial commit: ESP32-C3 WiFi→BLE bridge for Phomemo M110

- BLE client (NimBLE) with auto-scan/reconnect
- ESC/POS protocol encoder (GS v 0 raster)
- Web API: /api/status, /api/connect, /api/print
- Web UI: image upload with dithering, QR codes, positioning
- Client-side QR generation (qrcode-generator)
- Supports bitmap, QR, and raw ESC/POS print types

.gitignore

@@ -0,0 +1,7 @@
+.pio/
+.pioenvs/
+.vscode/
+*.o
+*.elf
+*.bin
+private_config.ini