[python] Drop poetry v1 support

[stephenfin]

This is a collection of individual changes that collectively bump the minimum version of poetry to v2, remove stuff that was only applicable for older versions, and migrates things from flake8 to ruff. This PR is likely easier to review on a commit-by-commit basis: I've tried to provide as much detail as possible about what I've done and why I did it in each commit, and the whole thing should be fully bisectable.

• [python] Re-generate samples
• [python] Drop fallback for poetry 1.x
• [python] Switch build backend to poetry-core
• [python] Remove setup.py file
• [python] Migrate from flake8 to ruff
• [python] Stop generating requirements.txt files by default
• bin/generate-samples: Remove warning about sleep

CC: @cbornet @tomplus @krjakbrjak @fa0311 @multani

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---

Summary by cubic

Drops Poetry v1 support and switches Python outputs to Poetry 2 with poetry-core, replacing setuptools scaffolding. Also migrates linting to Ruff and stops generating requirements.txt by default; samples and docs updated.

• Refactors

  • Require Poetry 2; set build-backend to poetry-core (PEP 517/621).
  • Remove setup.py/setup.cfg and related README instructions.
  • Migrate from flake8 to ruff; add basic ruff lint config; update test deps.
  • Generate requirements.txt and test-requirements.txt only when generateSourceCodeOnly is enabled; otherwise rely on pyproject.toml.
  • Update CLI help to reference project name in pyproject.toml.
  • Regenerate Python samples; drop legacy files (requirements.txt, setup.* , poetry.lock) and stale docs/tests.

• Migration

  • Use Poetry 2+ (poetry-core) for builds: pyproject.toml is the single source of truth.
  • Replace flake8/tox lint steps with ruff (ruff check/ruff format) in CI.
  • If you depended on setup.py/setup.cfg, move to pyproject.toml.
  • If you need requirements files, use source-only generation or create them from pyproject.

^{Written for commit ba7312c. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 97 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="modules/openapi-generator/src/main/resources/python/README_onlypackage.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/python/README_onlypackage.mustache:27">
P2: Typo: `requirement.txt` should be `requirements.txt` (missing 's'). This inconsistency would confuse users trying to follow the installation instructions.</violation>
</file>

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[cubic-dev-ai]

P2: Typo: requirement.txt should be requirements.txt (missing 's'). This inconsistency would confuse users trying to follow the installation instructions.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator/src/main/resources/python/README_onlypackage.mustache, line 27:

<comment>Typo: `requirement.txt` should be `requirements.txt` (missing 's'). This inconsistency would confuse users trying to follow the installation instructions.</comment>

<file context>
@@ -16,36 +16,24 @@ The `{{packageName}}` package is automatically generated by the [OpenAPI Generat
-* typing-extensions >= 4.7.1
+This python library package is generated without supporting files like `pyproject.toml`.
+To be able to use it, you will need these dependencies in your own package that uses this library.
+Requirements files (`requirement.txt`, `test-requirements.txt`) are provided for this.
+
+```
</file context>

Suggested change

	Requirements files (`requirement.txt`, `test-requirements.txt`) are provided for this.
	Requirements files (`requirements.txt`, `test-requirements.txt`) are provided for this.