JAWS: expose stop due to the minimum gap being reached to users

# Feature Description
As a use/instrument scientist I would like it to be clear when my jaws/slits/barn doors have[ stopped moving because a min gap has been reached](https://github.com/ISISComputingGroup/IBEX/issues/8505).

## Explanation
When a jaw blade is moving and the gap with the other in the pair reaches a minimum value, a stop command is issues. This stop command is not visible to the user. A recent patch [LINK here @Tom-Willemsen] has added a line to the log, but this will only be seen if the user/scientist goes looking and it should be made more apparent to them before they have to go for a logs. This should be apparent both when setting jaw positions in the GUI and with scripts.

### Additional Information

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# Acceptance Criteria

- [ ] When a user sets the positions of jaws in the GUI and the min gap is hit, some message visible to them
- [ ] When a user sets the positions of jaws in a script and the min gap is hit, some message is visible to them

# How to Review
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