Add docs/schema for Image Layer and Asset #76

	name: Test Schema
	on:
	- push
	- pull_request
	jobs:
	schema:
	runs-on: ubuntu-latest
	steps:
	-
	name: Checkout
	uses: actions/checkout@v4
	-
	name: Setup
	run: \|
	sudo apt update -q
	sudo apt install -yy python3 python3-pip graphviz
	pip install -r tools/requirements.txt
	-
	name: Validate
	run: \|
	make validate_full

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