Add a property to specify a log value to use for ThetaIn

- Add a new property, ThetaInLogName, to ReflectometryReductionOneAuto, which is used to find ThetaIn from the given log value.
- Note that if the ThetaIn property is also specified, that will take precedence.
- Add another new property, CorrectDetectors, to make it optional whether detectors are moved to ThetaIn (whether specified via ThetaIn or ThetaInLogValue). The default is true to maintain the previous behaviour when using ThetaIn.
- Pass through the overridden ThetaIn value to ReflectometryReductionOne. If ThetaIn is not specified, theta is calculated using SpecularReflectionCalculateTheta, and this is also now passed through for consistency. The latter does not work for some IDF setups but in those cases ThetaIn should be overridden with one of the above properties (and this no longer needs to affect the detector positions if CorrectDetectors is set to false).
- Disable the DetectorCorrectionType drop-down if CorrectDetectors is false.
- Disable the ReductionType drop-down if SummationType is SumInLambda.
- Improve an error message to report angles in degrees rather than radians.

Re #20397