tools: make `v check-md .` print the actual length of lines too, when reporting errors/warnings about them #35818

	name: Docs CI

	### Run on EVERY .v or .md related commit.
	### The documentation SHOULD stay valid, and the developers should receive
	### early warning, if they break it.

	on:
	push:
	paths-ignore:
	- '**.yml'
	- '!**/docs_ci.yml'
	- 'cmd/tools/vrepl.v'
	pull_request:
	paths-ignore:
	- '**.yml'
	- '!**/docs_ci.yml'
	- 'cmd/tools/vrepl.v'

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref == 'refs/heads/master' && github.sha \|\| github.ref }}
	cancel-in-progress: true

	jobs:
	check-markdown:
	runs-on: ubuntu-20.04
	timeout-minutes: 5
	steps:
	- uses: actions/checkout@v4
	- name: Build V
	run: make
	- name: Check markdown line length & code examples
	run: ./v check-md -hide-warnings .
	## NB: -hide-warnings is used here, so that the output is less noisy,
	## thus real errors are easier to spot.

	report-missing-fn-doc:
	runs-on: ubuntu-20.04
	timeout-minutes: 5
	env:
	MOPTIONS: --diff --deprecated --relative-paths --exclude /vlib/v/ --exclude /builtin/linux_bare/ --exclude /testdata/ --exclude /tests/
	steps:
	- uses: actions/checkout@v4
	- name: Build V
	run: make

	- name: Checkout previous v
	uses: actions/checkout@v4
	with:
	repository: vlang/v
	ref: master # important
	path: pv

	- name: Check against parent commit
	run: \|
	./v missdoc $MOPTIONS pv/vlib vlib

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