add stamp and dataclasses codegen #153

	# Example compatibility checks

	name: Compat

	on:
	pull_request:
	branches:
	- main

	jobs:
	compat:
	name: Check compatibility
	runs-on: ubuntu-latest
	steps:
	- name: Checkout current sources
	uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
	with:
	fetch-depth: 0

	- name: Find merge base with main
	id: merge_base
	run: \|
	git fetch origin main
	echo "MERGE_BASE=$(git merge-base HEAD origin/main)" >> $GITHUB_OUTPUT

	- name: Checkout stamp example schema from MERGE_BASE
	id: stamp_example
	run: \|
	if git cat-file -e "${{ steps.merge_base.outputs.MERGE_BASE }}:examples/stamp/schema-v2.json"; then
	cp examples/stamp/schema-v2.json examples/stamp/schema-v2.json.new
	git checkout ${{ steps.merge_base.outputs.MERGE_BASE }} -- examples/stamp/schema-v2.json
	echo "should_run=true" >> "$GITHUB_OUTPUT"
	else
	echo "should_run=false" >> "$GITHUB_OUTPUT"
	fi

	- name: Run jsoncompat ci
	if: steps.stamp_example.outputs.should_run == 'true'
	run: \|
	cargo run --bin jsoncompat ci examples/stamp/schema-v2.json examples/stamp/schema-v2.json.new

Provide feedback