1b8e51fbb4
- Send EAN via TCP first; use keyboard emulation only as fallback when TCP fails (POS_KEYBOARD_FALLBACK=0 disables it), so the register never receives the same code twice - Read POS host/port/timeout from POS_TCP_HOST, POS_TCP_PORT, POS_TCP_TIMEOUT; add GET /api/scanner_config - /api/detect reports object_present from background subtraction - Keep the scan lock until the scale is really empty (2 empty frames with calibrated background, 8 without) instead of releasing on one low-confidence frame - Set the scan lock before awaiting the send to avoid duplicate sends from frames arriving while the request is in flight - Keep HTTP status codes in /api/scan_ean (404/400, 502 on send failure) and run it in the thread pool since it does blocking I/O