feat: add siheng_servo SDK for D-AIS48025A servo driver

[zc-xzc]

Summary

Add Python SDK for Shanghai Siheng D-AIS48025A low-voltage servo driver, controlled via USB-RS485 using Modbus RTU protocol.

Hardware

• Driver: Siheng D-AIS48025A (DC 24-60V, 25A, RS485/CANopen)
• Motor: M60AIS117-24-C01330-B2-5-Z (24V, 0.4kW, 1.27Nm, 3000RPM)
• Interface: USB to RS485, baudrate 57600, Modbus RTU

Files (13 files, +4666 lines)

SDK package (siheng_servo_sdk/siheng_servo/)

• __init__.py - package exports
• constants.py - register address table (HXX_YY -> 0xXXYY)
• exceptions.py - 6 custom exception types
• client.py - SihengServo core client (speed/position/torque control, status)
• lift.py - LiftController for lift mechanism (up/down/stop/positioning)
• gui.py - PyQt5 GUI (speed slider, jog, emergency stop)

Tools & docs

• setup.py - pip install config (entry point: siheng-gui)
• example.py - 6 usage examples
• README.md - full documentation
• siheng_servo_gui.py - standalone GUI
• siheng_auto_scan.py - auto-scan driver comm params
• modbus_debug_gui.py - Modbus register probing tool
• stepper_motor_gui.py - generic stepper motor GUI

Key features

• Speed control: servo.run(500) / servo.stop() / servo.emergency_stop()
• Lift control: lift.up() / lift.down() / lift.move_to_height(50)
• Status monitoring: speed, position, torque, load, current, voltage, temp, fault
• Auto 16/32-bit data handling with configurable word order
• Context manager support

Test plan

• Package imports successfully
• Register address parsing verified (H06_03 -> 0x0603)
• GUI initialization tested
• Hardware communication test (baudrate 57600 confirmed)