DRAFT: Add face_edge_signs

[philipc2]

Closes #XXX

Overview

Expected Usage

import uxarray as ux

grid_path = "/path/to/grid.nc"
data_path = "/path/to/data.nc"

uxds = ux.open_dataset(grid_path, data_path)

# this is how you use this function
some_output = uxds.some_function()

# this is another way to use this function
other_output = uxds.some_function(some_param = True)

PR Checklist

General

• An issue is linked created and linked
• Add appropriate labels
• Filled out Overview and Expected Usage (if applicable) sections

Testing

• Adequate tests are created if there is new functionality
• Tests cover all possible logical paths in your function
• Tests are not too basic (such as simply calling a function and nothing else)

Documentation

• Docstrings have been added to all new functions
• Docstrings have updated with any function changes
• Internal functions have a preceding underscore (_) and have been added to docs/internal_api/index.rst
• User functions have been added to docs/user_api/index.rst

Examples

• Any new notebook examples added to docs/examples/ folder
• Clear the output of all cells before committing
• New notebook files added to docs/examples.rst toctree
• New notebook files added to new entry in docs/gallery.yml with appropriate thumbnail photo in docs/_static/thumbnails/