Expose background subtraction options in GUI

Allow z-axis limits and label to be changed by double-clicking on it in 3D plots.

Workbench crash after closing a plot then defining a new fit fn

Remove FrameworkManager.h from includes in any headers

It is a header that is heavy and should never be needed in another header.
It's long include chain now also has issues with older moc versions not
parsing nested namespaces

Also do some minor tidying of existing tests and add a missing polarization correction test.

Re #27826

Re #27826

Expose the background subtraction options in ReflectometryISISLoadAndProcess in the ISIS Reflectometry interface. The background processing instructions need to be specified on a per-angle basis so these are added to the Per-Angle Defaults table. The other options can be specified as defaults for all runs so are added as their own widgets on the Experiment Settings tab.

Re #27826

Equality for sample run

IndirectReduction GUI slowing processing on workbench when open.

NexusFileLoader class

This caused an issue with nested imports on Qt < 5.9

Fix bugs with restoring defaults on the reflectometry GUI

Merge branch 'master' of https://github.com/mantidproject/mantid into 28424_wb_brash_close_plot_then_define_new_fit_fn

# Conflicts:
#	qt/widgets/common/src/FitPropertyBrowser.cpp

Fix test_fitpropertybrowser unreliable test

Remove algorithm proxy class

Improve Status Information in Eng Diff GUI

Corrected Fermi and sample distance on MAPS for PyChop

Add mechanism to print exception in Kafka test thread

cancel algorithm when cancelling script in workbench