v1.1.3

Summary:
This release modernizes the project builds to use a pyproject.toml file and pixi. Spherical harmonic summations have been updated to use complex forms and np.einsum for linear algebra. The documentation has also been updated to parallel changes in the sister gravity-toolkit project.

Itemized Changes:

• docs: add badge for conda-forge
• docs: modernize documentation and builds (#36)
• refactor: use pyproject.toml for builds (#36)
• ci: use pixi for builds (#36)
• docs: use pixi for builds (#36)
• docs: add logo and color scheme (#36)
• docs: add project pages (#36)
• docs: use cards for front page (#36)
• docs: add release notes (#36)
• docs: convert install page to notebook (#36)
• refactor: ruff format (#36)
• fix: topographic_potential argument order (#37)
• fix: duplicate get_data_path in utilities (#37)
• fix: att_name in EGM2008 grids (#37)
• fix: coverage path in pyproject.toml (#37)
• refactor: use np.einsum for spherical harmonic summations (#38)
• refactor: use complex form of spherical harmonics for summations (#38)
• refactor: use np.radians to convert from degrees to radians (#38)
• feat: add interpolator for geoid grids (#39)
• feat: EGM2008 binary file can be compressed (#39)
• test: add interpolation test (#39)

Full Changelog: 1.1.2...1.1.3