Fix nanmax handling of empty and logical inputs

[sahilphad07-sudo]

nanmax did not correctly handle empty and logical inputs. Empty inputs could return NaN instead of preserving MATLAB-compatible empty outputs, while logical inputs caused an invalid conversion error because the implementation temporarily replaced values with -Inf and NaN.

This change updates nanmax to:

• Preserve the correct empty-array output shapes.
• Handle logical inputs using the underlying max behavior without converting logical values to NaN.
• Preserve existing behavior for numeric and other supported inputs.

Before

octave:1> nanmax ([])
ans = NaN

octave:2> nanmax (logical ([0 1 0]))
error: invalid conversion from NaN to logical

After

octave:1> nanmax ([])
ans = [](0x0)

octave:2> nanmax (logical ([0 1 0]))
ans = 1

MATLAB Behavior

>> nanmax([])
ans =

     []

>> nanmax(logical([0 1 0]))
ans =

  logical

   1

Regression Tests Added

• Empty input arrays and empty dimensions.
• Empty arrays with explicit dimensions.
• Empty arrays with 'all' and vecdim.
• Logical vector and matrix inputs.
• Logical inputs with explicit dimensions and 'all'.

Test Results

• Existing nanmax tests passes.
• Added regression tests pass.