Update inequality in get_linear_interpolated_value

[kavanase]

This is a small but important fix for the get_linear_interpolated_value function in pymatgen.util.coord, used in various places within the codebase.

This function works by finding the first index in x_values that is greater than / equal to x, and then uses this index and the previous (idx-1) with x_values and y_values to interpolate:
https://github.com/materialsproject/pymatgen/blob/v2025.2.18/src/pymatgen/util/coord.py#L136-L147

The issue is that if the first index in x_values is equal to x, this causes the ValueError to be thrown (as indices[0]==0); where it thinks that the input x to interpolate is outside the interpolable range. Changing the inequality to > rather than >= resolves this issue.

MWE:

from pymatgen.util.coord import get_linear_interpolated_value

get_linear_interpolated_value([0.0001, 0.0002], [1,2], 0.0001)

Current pymatgen master:

Where we can see "x=0.0001 is out of range of provided x_values (0.0001, 0.0002)" does not make sense.

This branch:

And confirming the error is still correctly thrown with an x value that is actually outside the range:

[kavanase]

Also there was a pre-commit codespell failure due to a variable name in local_env which was fixed in 8fdea16

[kavanase]

This also adds some very small updates to make the behaviour of DOS.get_interpolated_gap and Dos.get_interpolated_gap fully consistent

[mkhorton]

Thanks for catching and fixing this @kavanase! Appreciate the code readability improvements too.