protocol5: all packet types parsing covered with tests #6

	name: validate (lint) markdown files
	on: [push, pull_request]
	jobs:
	tests:
	runs-on: ubuntu-latest
	steps:
	- name: check out repository code
	uses: actions/checkout@v4

	# NOTE: heavy node.js is used only to run markdownlint - the same tool as in my editor (Visual Studio Code)

	# source: https://github.com/nodesource/distributions#debian-and-ubuntu-based-distributions
	- name: add node.js deb source
	run: \|
	sudo apt-get install -y ca-certificates curl gnupg && sudo mkdir -p /etc/apt/keyrings \
	&& curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key \| sudo gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg \
	&& NODE_MAJOR=20 \
	&& echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_$NODE_MAJOR.x nodistro main" \| sudo tee /etc/apt/sources.list.d/nodesource.list
	- name: install node.js
	run: sudo apt-get update && sudo apt-get install nodejs -y

	- name: install markdownlint-cli
	run: sudo npm install -g markdownlint-cli

	- name: validate all markdown files
	run: cd "${{ github.workspace }}" && ./tests/run-markdownlint.sh

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