Centre of mass callback

[jackbdoughty]

We could not use Bluesky's centre of mass callback as it was not suited for the way we would want to use it, so this is our implementation for one.

To test:

Make sure that all tests pass.
Run the following scans and check that you when you subscribe CoM callback, you get sensible CoMs for each. (Send me a message if you need to know how to set up to scan blocks against eachother / create fake data):

• A scan with non constant point spacing.
• A scan where some of the values are negative / have a background.
• The "there-and-back" scan so x points would be like: -2 -1 0 1 2 1 0 -1 -2. (Non continuous points)

[Copilot]

Pull Request Overview

This PR implements a custom CentreOfMass callback to calculate the centre of mass of a 2D area under the curve, replacing Bluesky's implementation for better suitability with disordered and non-continuous data.

• New CentreOfMass callback and corresponding tests have been added.
• Updates in the ISISCallbacks class and documentation to integrate the new callback.

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/callbacks/test_isis_callbacks.py	Adds tests to verify callback setup and error handling for CentreOfMass.
tests/callbacks/fitting/test_centre_of_mass.py	Provides comprehensive parameterized tests covering various data cases for CentreOfMass.
src/ibex_bluesky_core/callbacks/_fitting.py	Introduces the centre_of_mass_of_area_under_curve function and the CentreOfMass callback class.
src/ibex_bluesky_core/callbacks/init.py	Integrates CentreOfMass into the callbacks collection and ISISCallbacks properties.
doc/fitting/fitting.md	Updates documentation with a new section for the CentreOfMass callback.
doc/architectural_decisions/007-centre-of-mass.md	Documents the design decision to implement a custom CentreOfMass callback.

Comments suppressed due to low confidence (1)

doc/fitting/fitting.md:216

• The docs refer to a property named 'value' but the implementation uses 'result'. Please update the documentation to match the actual property name.

[`CentreOfMass`](ibex_bluesky_core.callbacks.CentreOfMass) has a property, `value` which stores the centre of mass value once the callback has finished.

[jackbdoughty]

Pull Request Overview

This PR implements a custom CentreOfMass callback to calculate the centre of mass of a 2D area under the curve, replacing Bluesky's implementation for better suitability with disordered and non-continuous data.

• New CentreOfMass callback and corresponding tests have been added.
• Updates in the ISISCallbacks class and documentation to integrate the new callback.

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file
Comments suppressed due to low confidence (1)

what he said fr

[rerpha]

as above i don't think this wants to be in fitting, but i think that the fitting section could do with a rework as it has callbacks in at the moment - we should move them to the callbacks header as with the CentreOfMass cb. Also I need to add #244 to it (probably wants to be the first page!)

[Tom-Willemsen]

I'll refactor fitting to be entirely under the callbacks header I think.

[Tom-Willemsen]

will fix in documentation mega-pr