docs: add license headers and spdx id #29

	name: CI build
	on:
	pull_request:

	jobs:
	build-and-test:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v3
	with:
	fetch-depth: 0

	- name: Install sodium
	run: sudo apt-get install -y libsodium-dev

	- name: Setup Go
	uses: actions/setup-go@v1
	with:
	go-version: 1.19

	- name: Build
	run: make build

	- name: Test
	run: make test

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