v0.12.0i13: lossless encode-effort knob (ratio ↔ speed) #399

	name: CI

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]

	permissions:
	contents: read
	checks: write

	jobs:
	build-and-test:
	name: Build & test (macOS)
	runs-on: macos-15
	timeout-minutes: 25
	steps:
	- uses: actions/checkout@v4

	- name: Show toolchain
	run: \|
	swift --version
	sw_vers

	- name: Install libjxl + pkg-config
	run: \|
	brew update
	brew install jpeg-xl pkg-config

	- name: Build (release)
	run: swift build -c release

	- name: Test
	run: swift test -c release

	- name: CLI smoke test
	run: \|
	# Generate a small synthetic PNG, encode + decode through jxl-tool,
	# then verify libjxl can decode the same .jxl (cross-codec sanity).
	mkdir -p /tmp/ci
	python3 - <<'PY'
	import struct, zlib
	w, h = 32, 32
	raw = b''.join(b'\x00' + bytes((x + y) & 0xff for x in range(w)) for y in range(h))
	def chunk(t, d):
	return struct.pack('>I', len(d)) + t + d + struct.pack('>I', zlib.crc32(t + d))
	ihdr = chunk(b'IHDR', struct.pack('>IIBBBBB', w, h, 8, 0, 0, 0, 0))
	idat = chunk(b'IDAT', zlib.compress(raw))
	iend = chunk(b'IEND', b'')
	open('/tmp/ci/in.png', 'wb').write(b'\x89PNG\r\n\x1a\n' + ihdr + idat + iend)
	PY
	.build/release/jxl-tool --version
	.build/release/jxl-tool encode --input /tmp/ci/in.png --output /tmp/ci/out.jxl --lossless --effort 5
	/opt/homebrew/bin/djxl /tmp/ci/out.jxl /tmp/ci/ref.png
	.build/release/jxl-tool decode --input /tmp/ci/out.jxl --output /tmp/ci/recovered.png

	- name: Lint - no leftover NIfTI references
	run: \|
	# Should be 0 — the NIfTI feature was rolled back.
	! grep -rni 'nifti\\|\\.nii' Sources Tests 2>/dev/null

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