Dem-stitcher

Fixed
* Ruff linting and formatting
* In-memory merge of files - preserving nodata and dtypes correctly

Added
* Tests for in-memory merge
* Tests for crop profile
* Allows users to specify `dst_tile_dir` for location of tiles
* Allows users to specify `overwrite_existing_tiles` for overwriting existing tiles (should tiles need to be re-used in the same directory)

Removed
* Dependency of environment.yml on anaconda and default distributions (now only `conda-forge`). This is purely ascethetic as the package's highest priority channel is `conda-forge`.

Fixed
* Python 3.13 compatibility (was not listed properly in pyproject.toml)

Fixed
* 3.9 compatibility due to 3.10+ type hints.
* Adds 3.13 compatibility.
* Fixes the github action for tests to correctly use python versions specified by the matrix

Changed
* Removes `|` in type hints for 3.9 compatibility.

Added
* Uses ruff exclusively for linting and formatting following OPERA/ARIA linting standards from DIST-S1.
* Added `geoid_path` to `stitch_dem` to allow for user to specify geoid path. If None, then default geoid is used.
* Added UserWarning when geoid file does not cover the dateline.

Changed
* Updated `geoid.py` to use the new geoid path for egm08 with 1 arc-second resolution.
* Library is in `src` directory per: https://packaging.python.org/en/latest/discussions/src-layout-vs-flat-layout/
* Helps with Ruff, too.

Fixed
* Allows users to bring their own geoid data as noted [here](https://github.com/ACCESS-Cloud-Based-InSAR/dem-stitcher/issues/100).
* Ruff linting and docstring issues using the new ruff configuration
* Updates test action workflow with micromamba action.

Removed
* Removed explicit flake8 action (should be handled by ruff).

Fixed
* Resolves read_geoid issue [here](https://github.com/ACCESS-Cloud-Based-InSAR/dem-stitcher/issues/96).
* Update geoid url for egm08 (again) creating public bucket for ACCESS processing
* Included egm96 as gtx in the data directory
* egm08 and egm96 data comes from here: https://download.osgeo.org/proj/vdatum/

Fixed
* Check for Earthdata credentials in netrc (adapted from Joe Kennedy/Forrest Williams) resolving isse [83](https://github.com/ACCESS-Cloud-Based-InSAR/dem-stitcher/issues/83)
* when no credentials in netrc are present when requesting data for `nasadem` or `srtm_v3`, there is a human readable error instructing user to update their `~/.netrc`.
* Updates some ruff linting
* Ensures ruff in `environment.yml`
* Ensure single quotes for consistency.
Changed
* egm08 is now using 2.5 deg raster rather than 1 deg.