Add workflow to build firmware #3

	name: Build Firmware

	on:
	push: # Trigger for pushes.
	paths:
	- hardware/firmware/**
	- .github/workflows/build-firmware.yaml
	pull_request: # Trigger for pull requests.
	types: [opened, synchronize, reopened, ready_for_review]
	workflow_dispatch: # Allows for manual triggering.
	inputs:
	ref:
	description: "The ref to build and test."
	required: false

	# If another instance of this workflow is started for the same PR, cancel the
	# old one. If a PR is updated and a new test run is started, the old test run
	# will be cancelled automatically to conserve resources.
	concurrency:
	group: ${{ github.workflow }}-${{ inputs.ref \|\| github.ref }}
	cancel-in-progress: true

	jobs:
	build:
	name: Build Firmware
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	with:
	ref: ${{ inputs.ref \|\| github.ref }}

	- name: Install Arduino CLI
	uses: arduino/setup-arduino-cli@v1

	- name: Install Arduino RP2040 core
	run: \|
	arduino-cli config add board_manager.additional_urls https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
	arduino-cli core update-index
	arduino-cli core install rp2040:rp2040

	- name: Install Arduino libraries
	run: arduino-cli lib install Ethernet

	- name: Build firmware
	run: \|
	cd hardware/firmware
	make build

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