Add option to ignore masked pixels in integration algorithms and improve skew background determination

[RichardWaiteSTFC]

Description of work

This work comprises 2 improvements to single-crystal integration methods:

1. When determining background bins by minimising third moment (skew) in IntegratePeaksSkew - ensure loop terminates if skew < 0 (we expect minimum skew of background to be 0 - for low counts it should in fact be positive)
2. Add option to ignore peaks for which mask (or shoebox etc.) includes a masked detector - this affects
   • IntegratePeaksSkew
   • IntegratePeaksShoeboxTOF
   • IntegratePeaks1DProfile

Purpose of work

Change (1) stops peak mask of IntegratePEaksSkew including too many pixels due to small diffuse scattering - see issue #37105

Change (2) allows the user to make a custom mask for edges (or dodgy tube etc.) - whereas NcolsEdge and NRowsEdge are assumed to be the same for all banks. To support this functionality the minimum value for NrowsEdge and NColsEdge has been decreased to 0 - i.e. it is now possible to only define edges using masked detectors on the workspace. Note this is how detector edges are denoted in other integration algorithms such as IntegratePeaksMD.

Fixes #37105

To test:

(1) Run this script

ws = Load(Filename=r'C:\mantid-conda\mantid\build\ExternalData\Testing\Data\DocTest\SXD23767.raw', OutputWorkspace='SXD23767')
# peaks = FindSXPeaksConvolve(InputWorkspace='SXD23767', PeaksWorkspace='peaks_out', ThresholdIoverSigma=4, GetNBinsFromBackToBackParams=True, NFWHM=6, PeakFindingStrategy='VarianceOverMean', ThresholdVarianceOverMean=1.25)

peaks = CreatePeaksWorkspace(InstrumentWorkspace=ws, NumberOfPeaks=0, OutputWorkspace="peaks_out")
pk_pos = [(3169, 1851.59), (752, 2292.94), (1971, 3169.28), (3633, 4623.41), (6469, 1531.5)]
for detid, tof in pk_pos:
    AddPeak(PeaksWorkspace=peaks, RunWorkspace=ws, TOF=tof, DetectorID=detid, EnableLogging=False)
                    
skew_params = {'UseNearestPeak': True, 'IntegrateIfOnEdge': False,
             'NRowsEdge': 1, 'NColsEdge': 1, 
             'LorentzCorrection': True,
             'NVacanciesMax': 2, 'NPixPerVacancyMin': 2, 'NTOFBinsMin': 2,
             'UpdatePeakPosition': False, 'OptimiseMask': True,
             'GetTOFWindowFromBackToBackParams': False, 
              'ScaleThetaWidthByWavelength': True,
             'BackScatteringTOFResolution': 0.035, 'ThetaWidth': 1.5,
             'OptimiseXWindowSize':True, 'ThresholdIoverSigma': 20}
skew_params['OutputFile'] = rf"C:\Users\xhg73778\Desktop\{ws.name()}_peaks_skew_zero_skew.pdf"
peaks_int = IntegratePeaksSkew(InputWorkspace=ws, PeaksWorkspace=peaks, **skew_params)

(2) Open the pdf output and check the mask still covers the peaks (should look like the left hand column in the screenshots above)

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