[eigen] add eigen backend indirection #1812

	name: 'Format'

	on:
	push:
	branches: [ 'master' ]
	pull_request:
	branches: [ 'master' ]
	schedule:
	- cron: '0 0 * * */5'

	permissions:
	contents: read

	jobs:
	build:
	runs-on: ubuntu-24.04
	steps:
	- name: Harden Runner
	uses: step-security/harden-runner@0080882f6c36860b6ba35c610c98ce87d4e2f26f # v2.10.2
	with:
	egress-policy: audit
	- name: 'Checkout'
	uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
	- name: 'Install'
	run: sudo apt install cmake-format
	- name: 'Test'
	run: \|
	find . \
	-iname '*.hpp' \
	-o -iname '*.tpp' \
	-o -iname '*.cpp' \
	-o -iwholename './support/generator/generator' \
	\| xargs \
	clang-format-18 --Werror --dry-run --verbose -style=file
	find . \
	-iname 'CMakeLists.txt' \
	-o -iname '*.cmake.in' \
	\| xargs \
	cmake-format --check

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