Write a CONTRIBUTING.md document in English #26

	name: CI

	on:
	pull_request:
	push:
	branches:
	- main
	workflow_dispatch:

	permissions:
	contents: read

	jobs:
	fmt:
	name: fmt (gofmt)
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version-file: go.mod
	cache: true

	- name: Verify formatting
	run: \|
	files=$(gofmt -l .)
	if [ -n "$files" ]; then
	echo "These files are not gofmt-formatted:"
	echo "$files"
	exit 1
	fi

	lint:
	name: lint (go vet)
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version-file: go.mod
	cache: true

	- name: Run go vet
	run: go vet ./...

	test:
	name: test (go test)
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version-file: go.mod
	cache: true

	- name: Run tests
	run: go test ./...

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