chore: add black, ruff, mypy and pre-commit configuration

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: nos1dot618

.pre-commit-config.yaml

@@ -0,0 +1,34 @@
+# Install with `pre-commit install`; run on everything with `pre-commit run --all-files`.
+# The Python tools come from requirements-dev.txt, so CI and your machine use
+# the same versions.
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v5.0.0
+    hooks:
+      - id: trailing-whitespace
+      - id: end-of-file-fixer
+      - id: mixed-line-ending
+        args: [--fix=lf]
+      - id: check-merge-conflict
+      - id: check-toml
+      - id: check-yaml
+      - id: check-added-large-files
+
+  - repo: local
+    hooks:
+      - id: black
+        name: black
+        entry: black
+        language: system
+        types: [python]
+      - id: ruff
+        name: ruff
+        entry: ruff check --fix
+        language: system
+        types: [python]
+      - id: mypy
+        name: mypy
+        entry: mypy
+        language: system
+        types: [python]
+        pass_filenames: false

pyproject.toml

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+# Settings for the tools that check the build scripts. The site itself is
+# built with `python build.py`; it isn't a package.
+
+[project]
+name = "lambda-discipline-website"
+version = "0"
+requires-python = ">=3.11"
+
+[tool.black]
+target-version = ["py311"]
+
+[tool.ruff]
+target-version = "py311"
+extend-exclude = [".cache", "_site"]
+
+[tool.ruff.lint]
+select = [
+    "E", "W", "F",  # pycodestyle and pyflakes
+    "I",            # import order
+    "UP",           # modern syntax
+    "B",            # likely bugs
+    "SIM",          # simplifications
+    "RUF",          # ruff's own rules
+]
+ignore = [
+    "E501",         # black decides line length
+]
+
+[tool.mypy]
+files = ["build.py", "lbd_lexer.py"]
+python_version = "3.11"
+strict = true
+# Some ignores in the scripts are for editors' type checkers, not mypy.
+warn_unused_ignores = false

requirements-dev.txt

@@ -0,0 +1,8 @@
+# Tools for checking the build scripts; CI runs the same versions.
+-r requirements.txt
+black==26.10.1
+mypy==2.4.0
+pre-commit==4.6.0
+ruff==0.17.1
+types-Markdown==3.10.2.20261007
+types-Pygments==2.21.0.20260819