chore(release): 9.0.0 [skip ci]

# [9.0.0](https://gitlab.com/to-be-continuous/python/compare/8.6.0...9.0.0) (2025-11-22)

### Features

* harmonize Python CLI arguments configuration ([b4ede578](https://gitlab.com/to-be-continuous/python/commit/b4ede57865ca553e4ab7ca3797514c3afe6ca288)

)

### BREAKING CHANGES

* Changed default arguments and behavior for Python tools

This commit refactors how file paths and arguments are provided to Python tools (pylint, black, isort, mypy, ruff) to improve consistency and align with .gitignore-based exclusion patterns.

Breaking changes:
- pylint: pylint-files variable now defaults to "." instead of auto-discovering Python files
- pylint: Merged pylint-files and pylint-args into single pylint-args parameter
- mypy: mypy-files variable now defaults to "." instead of auto-discovering Python files
- mypy: mypy-args now defaults to "--exclude /.cache/ --exclude /.venv/ ." instead of empty
- mypy: Merged mypy-files and mypy-args into single mypy-args parameter

Migration guide:
- If you were using pylint-files, merge it into pylint-args
- If you were using mypy-files, merge it into mypy-args
- If you were relying on auto-discovery of Python files, explicitly set paths in args variables
- Ensure .gitignore properly excludes .cache/ and .venv/ directories (recommended)

Rationale:
This change improves consistency across all Python tools by:
- Using a single parameter combining files and CLI options instead of splitting them
- Leveraging .gitignore for exclusions to avoid duplicate configuration
- Making default behavior explicit (analyze current directory ".")

Additional improvements:
- black: Added black-args variable (defaults to "--diff .") to allow argument customization
- isort: Added isort-args variable (defaults to ".") to allow argument customization
- All tools: File exclusions now leverage .gitignore instead of tool-specific --exclude options
- Add ${TRACE} variable management to many commands for allow verbose output when debugging
- Create .cache directory with .gitignore entry during initialization
- Remove unnecessary argument from ruff (can run without explicit "." parameter)

Co-authored-by: Guilhem Bonnefille <guilhem.bonnefille@csgroup.eu>
Co-authored-by: Gaëtan Montury <10528250-pytgaen@users.noreply.gitlab.com>
Co-authored-by: Pierre Smeyers <pierre.smeyers@gmail.com>