[pre-commmit] adds hook + config for markdown lint

.markdownlint.yml

+---
+###########################
+###########################
+## Markdown Linter rules ##
+###########################
+###########################
+
+# Linter rules doc:
+# - https://github.com/DavidAnson/markdownlint
+
+###############
+# Rules by id #
+###############
+MD013:
+  line_length: 120 # Line length 80 is far to short
+MD041: false # require heading as first line in file
+MD040: false # ``` fenced code must have language set
+
+#################
+# Rules by tags #
+#################
+blank_lines: false  # Error on blank lines

.pre-commit-config.yaml

@@ -20,3 +20,7 @@ repos:
     - id: ruff
       # Respect `exclude` and `extend-exclude` settings.
       args: ["--force-exclude", "--fix"]
+- repo: https://github.com/DavidAnson/markdownlint-cli2
+  rev: v0.4.0
+  hooks:
+  - id: markdownlint-cli2