Rework storage to an interface; add tests for `jmm models` #12

	name: Validate PRs

	on:
	pull_request:
	branches: [ main ]

	jobs:
	go:
	name: Check sources
	runs-on: ubuntu-20.04
	steps:
	- name: Checkout code
	uses: actions/checkout@v4

	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version: 1.21.6

	- name: Check go.mod
	run: \|
	go mod tidy
	if ! git diff --quiet; then
	echo "Go modules need tidying (go mod tidy)"
	exit 1
	fi

	- name: Check format
	run: \|
	go fmt ./...
	if ! git diff --quiet; then
	echo "Files are not formatted (go fmt ./...)"
	exit 1
	fi

	- name: Check build
	run: \|
	if ! go build; then
	echo "Project does not build"
	exit 1
	fi

	- name: Run tests
	run: \|
	if ! go test ./... -v; then
	echo "Project tests failed"
	exit 1
	fi

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