gh-39694: Ruff: move config to `pyproject.toml`
    
Move config from ruff to `pyproject.toml` to fix some issues with VSCode
and to reduce cluttering in the root.

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URL: #39694
Reported by: Tobias Diez
Reviewer(s): Frédéric Chapoton

Author: Release Manager

Diff for: .vscode/settings.json

@@ -107,7 +107,9 @@
         "zmax",
         "zmin"
     ],
-    "editor.formatOnType": true,
+    "[python]": {
+        "editor.defaultFormatter": "charliermarsh.ruff"
+    },
     "esbonio.sphinx.confDir": "",
     // Don't update the settings.json file with values inferred from Meson (we provide them manually)
     "mesonbuild.modifySettings": false,

Diff for: pyproject.toml

@@ -183,3 +183,25 @@ dev = [
   "grayskull",
   "toml",
 ]
+
+[tool.ruff]
+# https://docs.astral.sh/ruff/configuration
+
+# Python 3.11 is the minimum supported version
+target-version = "py311"
+
+[tool.ruff.lint]
+select = [
+  "E", # pycodestyle errors - https://docs.astral.sh/ruff/rules/#error-e
+  "F", # pyflakes - https://docs.astral.sh/ruff/rules/#pyflakes-f
+  "I", # isort - https://docs.astral.sh/ruff/rules/#isort-i
+  "PL", # pylint - https://docs.astral.sh/ruff/rules/#pylint-pl
+]
+ignore = [
+  "E501", # Line too long - hard to avoid in doctests, and better handled by black.
+]
+
+[tool.ruff.lint.per-file-ignores]
+"all.py" = [
+  "F401", # Unused import - these files are by definition collections of imports.
+]