Chore/update linting tools

[mcocdawc]

• manually fix the remaining linting errors; requires discussion with reviewers/maintainers.

Description

Updated and unified the pre-commit hooks in all earthkit packages.
Some of them were failing the test suite just because of the pre-commit hooks.
Fixing this it was a good opportunity to unify settings.

Uses now ruff for formatting (former black), linting, and import sort (former isort)

The following PRs do the same changes in all the earthkit packages:

• Chore/update linting tools earthkit-climate#43
• Chore/update linting tools earthkit-data#927
• Chore/update linting tools earthkit-geo#39
• Chore/update linting tools earthkit-hydro#178
• Chore/update linting tools earthkit-meteo#125
• Chore/update linting tools #176
• Chore/update linting tools earthkit-time#14
• Chore/update linting tools earthkit-transforms#87
• Chore/update linting tools earthkit-workflows#173

In earthkit-plots in particular, it prevents now directly pushing to develop and checks the pre-commit hooks as part of the CI.

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Add the mpl references for tests and remove the directory from the .gitignore.

The only remaining failing tests are:

FAILED tests/images/test_healpix.py::test_healpix_interpolated - ImportError: Regridding not available. Please install the earthkit-regrid package.
FAILED tests/images/test_healpix.py::test_healpix_pixels - ImportError: The healpix plotting backend requires the healpy package.
FAILED tests/images/test_octahedral.py::test_octahedral_interpolated - ImportError: Regridding not available. Please install the earthkit-regrid package.

As the earthkit-regrid package is deprecated AFAIK, I don't know if the 1st and 3rd test should be fixed or simply removed.
Re the 2nd test. Either healpy should be added as a strict dependency, or the test should only be executed if healpy is installed. That's a call one of the maintainers has to make.

Contributor Declaration

By opening this pull request, I affirm the following:

• All authors agree to the Contributor License Agreement.
• The code follows the project's coding standards.
• I have performed self-review and added comments where needed.
• I have added or updated tests to verify that my changes are effective and functional.
• I have run all existing tests and confirmed they pass.

[mcocdawc]

@JamesVarndell The remaining failing tests already fail in develop as well. Fixing in #177

[Copilot]

Pull request overview

This PR standardizes linting/formatting across the project by migrating pre-commit hooks and code style tooling to Ruff, and applies the resulting formatting changes across source, tests, and documentation notebooks.

Changes:

• Replaced Black/isort-driven formatting with Ruff (ruff-check + ruff-format) and added Ruff configuration to pyproject.toml.
• Updated .pre-commit-config.yaml to run Ruff linting/fixes and Ruff formatting.
• Applied formatting-only updates across Python sources, tests, and many Jupyter notebooks to match the new style.

Reviewed changes

Copilot reviewed 111 out of 113 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
tests/utils/test_string_utils.py	Ruff formatting updates in tests.
tests/test_schemas.py	Ruff formatting updates in tests.
tests/test_identifiers.py	Ruff formatting updates in tests.
tests/styles/test_style_features.py	Ruff formatting updates in tests.
tests/sources/test_xarray.py	Ruff formatting updates in tests.
tests/sources/test_numpy.py	Ruff formatting updates in tests.
tests/metadata/test_formatters.py	Ruff formatting updates in tests.
tests/interactive/test_polar.py	Ruff formatting updates in tests.
tests/images/test_mulitple_layers.py	Ruff formatting updates in image tests.
tests/images/test_anemoi_use_case.py	Ruff formatting updates in image tests.
tests/geo/test_natural_earth.py	Ruff formatting updates in geo tests.
tests/geo/test_grids.py	Ruff formatting updates in geo tests.
tests/geo/test_geometry.py	Ruff formatting updates in geo tests.
tests/geo/test_domains.py	Ruff formatting updates in geo tests.
tests/components/test_figures.py	Minor docstring casing/formatting updates in tests.
src/earthkit/plots/styles/levels.py	Ruff formatting updates in style levels.
src/earthkit/plots/styles/legends.py	Ruff formatting updates in legends helpers.
src/earthkit/plots/styles/colors/init.py	Docstring punctuation tweak.
src/earthkit/plots/styles/init.py	Ruff formatting updates in core Style implementation.
src/earthkit/plots/sources/extractors/xarray.py	Ruff formatting updates in xarray extractor.
src/earthkit/plots/sources/extractors/numpy.py	Ruff formatting updates in numpy extractor.
src/earthkit/plots/sources/extractors/earthkit.py	Ruff formatting updates in earthkit extractor.
src/earthkit/plots/sources/init.py	Ruff formatting updates in Source/dimension handling.
src/earthkit/plots/shortcuts.py	Ruff formatting updates to shortcuts helpers.
src/earthkit/plots/schemas.py	Ruff formatting updates in schema utilities.
src/earthkit/plots/resample.py	Ruff formatting updates in resampling utilities.
src/earthkit/plots/quickplot.py	Formatting changes + docstring line wrapping.
src/earthkit/plots/quickmap.py	Formatting changes + docstring punctuation.
src/earthkit/plots/plottypes/statistics.py	Docstring punctuation + formatting updates.
src/earthkit/plots/metadata/labels.py	Ruff formatting updates in label helpers.
src/earthkit/plots/metadata/formatters.py	Ruff formatting updates in metadata formatters.
src/earthkit/plots/interactive/polar.py	Ruff formatting updates in polar plotting.
src/earthkit/plots/interactive/inputs.py	Ruff formatting updates in interactive inputs utilities.
src/earthkit/plots/interactive/heat.py	Ruff formatting updates in interactive heatmap.
src/earthkit/plots/interactive/charts.py	Ruff formatting updates in interactive chart class.
src/earthkit/plots/interactive/box.py	Ruff formatting updates in interactive box plot.
src/earthkit/plots/identifiers.py	Ruff formatting updates in identifier helpers.
src/earthkit/plots/geo/regrid.py	Ruff formatting updates in regridding helpers.
src/earthkit/plots/geo/optimisers.py	Docstring + formatting updates.
src/earthkit/plots/geo/octahedral.py	Formatting + docstring section header normalization.
src/earthkit/plots/geo/natural_earth.py	Ruff formatting updates in Natural Earth helpers.
src/earthkit/plots/geo/healpix.py	Formatting + minor docstring punctuation.
src/earthkit/plots/geo/grids.py	Ruff formatting updates in grids helpers.
src/earthkit/plots/geo/gisco.py	Ruff formatting updates in GISCO helpers.
src/earthkit/plots/geo/geometry.py	Ruff formatting updates in geometry helpers.
src/earthkit/plots/geo/domains.py	Ruff formatting updates in Domain helpers.
src/earthkit/plots/geo/coordinate_reference_systems.py	Ruff formatting updates in CRS helpers.
src/earthkit/plots/geo/bounds.py	Ruff formatting updates in bounds helpers.
src/earthkit/plots/components/ticks.py	Formatting/docstring wrapping updates.
src/earthkit/plots/components/subplots.py	Formatting/docstring wrapping updates.
src/earthkit/plots/components/maps.py	Formatting/docstring wrapping updates.
src/earthkit/plots/components/layouts.py	Formatting cleanup.
src/earthkit/plots/components/layers.py	Formatting/docstring compacting updates.
src/earthkit/plots/components/figures.py	Formatting/docstring wrapping updates.
src/earthkit/plots/components/extractors.py	Formatting updates in plotting extractors.
src/earthkit/plots/cli/parsers.py	Formatting updates in YAML CLI parser.
src/earthkit/plots/ancillary.py	Formatting updates in ancillary loader errors.
pyproject.toml	Remove isort config; add Ruff configuration (line length, lint selects/ignores).
docs/examples/sandbox.ipynb	Notebook formatting (quotes/whitespace).
docs/examples/reduced_gg.ipynb	Notebook formatting (expressions/whitespace).
docs/examples/guide/figures-and-subplots.ipynb	Notebook formatting (imports/quotes).
docs/examples/guide/06-reusable-code.ipynb	Notebook whitespace formatting.
docs/examples/guide/04-styles.ipynb	Notebook whitespace formatting.
docs/examples/guide/03-components.ipynb	Notebook whitespace + expression formatting.
docs/examples/gallery/vector-data/vector-styles.ipynb	Notebook formatting (string concatenation).
docs/examples/gallery/vector-data/Untitled.ipynb	Notebook formatting/cleanup.
docs/examples/gallery/time-series/timeseries.ipynb	Notebook formatting (trailing commas).
docs/examples/gallery/time-series/simple-line.ipynb	Notebook import ordering/spacing.
docs/examples/gallery/time-series/global-average-temperature.ipynb	Notebook formatting (imports + long lines).
docs/examples/gallery/time-series/era5-precip.ipynb	Notebook formatting (trailing commas + spacing).
docs/examples/gallery/time-series/cmip6.ipynb	Notebook formatting (quotes + line wrapping).
docs/examples/gallery/tiles/tiles.ipynb	Notebook content changed (cells emptied).
docs/examples/gallery/point-data/usa-temperature-obs.ipynb	Notebook formatting (long call collapsed).
docs/examples/gallery/point-data/satellite-level2-co2.ipynb	Notebook formatting (kwargs spacing).
docs/examples/gallery/interactive/meteogram.ipynb	Notebook formatting (import order + quotes).
docs/examples/gallery/hovmoeller/hovmoeller.ipynb	Notebook formatting (import ordering + call wrapping).
docs/examples/gallery/gridded-data/weather-forecast-steps.ipynb	Notebook formatting (imports + long call wrapping).
docs/examples/gallery/gridded-data/vorticity-over-andes.ipynb	Notebook formatting (list layout + expressions).
docs/examples/gallery/gridded-data/unstructured-grids.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/gridded-data/true-color-satellite.ipynb	Notebook formatting (imports + dict quoting).
docs/examples/gallery/gridded-data/time-zones.ipynb	Notebook formatting (quotes/spacing).
docs/examples/gallery/gridded-data/temperature-and-pressure.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/gridded-data/numpy-arrays.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/gridded-data/model-orography.ipynb	Notebook formatting (expression spacing).
docs/examples/gallery/gridded-data/hatched-shading.ipynb	Notebook formatting (string repetition spacing).
docs/examples/gallery/gridded-data/globe.ipynb	Notebook formatting (imports + dict quoting).
docs/examples/gallery/gridded-data/el-nino.ipynb	Notebook formatting (call wrapping).
docs/examples/gallery/gridded-data/efas.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/gridded-data/categorical-data.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/grid-types/reduced-gg-point-cloud.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/grid-types/reduced-gg-interpolated.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/grid-types/reduced-gg-grid-cells.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/grid-types/octahedral-cells.ipynb	Notebook formatting (escape handling).
docs/examples/gallery/grid-types/healpix-point-cloud.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/grid-types/healpix-pixels.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/grid-types/healpix-interpolated.ipynb	Notebook formatting (imports/spacing).
docs/examples/gallery/domains/domain-union.ipynb	Notebook formatting (quotes/spacing).
docs/examples/gallery/domains/cartopy-crs.ipynb	Notebook formatting (import order/spacing).
docs/examples/gallery/animation.ipynb	Notebook formatting (imports + quotes).
docs/examples/examples/vectors-styles.ipynb	Notebook formatting (string concatenation).
docs/examples/examples/unstructured-data.ipynb	Notebook formatting (spacing + trailing commas).
docs/examples/examples/string-formatting-units.ipynb	Notebook whitespace + string concatenation formatting.
docs/examples/examples/string-formatting-time.ipynb	Notebook formatting (string concatenation).
docs/examples/examples/plotting-and-styling-vector-data.ipynb	Notebook import ordering formatting.
docs/examples/examples/plotting-and-styling-isolines.ipynb	Notebook formatting (trailing commas + call layout).
docs/examples/examples/isolines-basics.ipynb	Notebook comment spacing formatting.
docs/examples/examples/interactive-windrose-plot.ipynb	Notebook formatting (imports, quotes, long calls).
docs/examples/examples/interactive-line-plot.ipynb	Notebook formatting (quotes + long lines).
docs/examples/examples/interactive-heatmap-plot.ipynb	Notebook formatting (quotes + wrapping).
docs/examples/examples/interactive-bar-plot.ipynb	Notebook formatting (spacing + dict layout).
docs/examples/ads.ipynb	Notebook formatting (quotes + call layout).
docs/Untitled.ipynb	Notebook formatting (trailing commas).
.pre-commit-config.yaml	Replace Black/isort hooks with Ruff check/format hooks; update other hook revisions.

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