Check stepper alarm status after move

[alexdewar]

Description

The ST10 controller has an "alarm status" that can be queried to find out if an error has occurred. This includes drive faults, low voltage etc. as well as if the motor has hit a limit switch (which was the original motivation for looking at this -- currently we just hardcode the position of the limits in FROG so we don't hit them). Jon has said that he might not put limit switches on the new UNIRAS rig, in which case we could just turn them off, but in any case it seems useful to know whether something's gone wrong with the motor, especially if you're 10,000 ft up.

When an error occurs, we should get a notification because the motor will stop so it makes sense to query the motor at this point.

Closes #703.

Type of change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Documentation (non-breaking change that adds or improves the documentation)
• Optimisation (non-breaking, back-end change that speeds up the code)

Key checklist

• Pre-commit hooks run successfully (pre-commit run -a)
• All tests pass (pytest)
• The documentation builds without warnings (mkdocs build -s)
• Check the GUI still works (if relevant)
• Check the code works with actual hardware (if relevant)
• Check the pyinstaller-built executable works (if relevant)

Further checks

• Code is commented, particularly in hard-to-understand areas
• [xgg] Tests have been added or an issue has been opened to tackle that in the future. (Indicate issue here: # (issue))

[Copilot]

Pull Request Overview

This PR adds functionality to check the stepper motor controller’s alarm status after a move. It introduces a new ST10AlarmCode enum, updates signal handling to check the alarm state before sending a move-end message, and adds a utility method for converting responses to integers.

• Added a new ST10AlarmCode IntFlag enum to encapsulate alarm bit flags.
• Modified the move end handling to call _on_move_end which checks the alarm state.
• Introduced the _request_int method to simplify numeric conversions from device responses.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tests/hardware/plugins/stepper_motor/test_st10_controller.py	Updated tests to reflect the new _on_move_end handler and added tests for the alarm_code property.
frog/hardware/plugins/stepper_motor/st10_controller.py	Introduced ST10AlarmCode enum, _on_move_end logic for alarm checking, and a new _request_int method for integer conversion.

Comments suppressed due to low confidence (1)

frog/hardware/plugins/stepper_motor/st10_controller.py:532

• [nitpick] Consider including the requested variable name (e.g., '{name}') in the exception message to improve debugging clarity. For example, change the error message to 'Non-integer response received for {name}: {resp}'.

return int(resp, base)

[dc2917]

Seems sensible, and looks good overall! Just made a couple of suggestions, and wondering whether we're missing some tests

[dc2917]

No test for ST10Controller._request_int?

[alexdewar]

I've added one now as well as one for _on_move_end