Caddy server: enable CORS for any domain

Caddyfile

(cors) {
	@cors_preflight method OPTIONS

	header {
		Access-Control-Allow-Origin "{header.origin}"
		Vary Origin
		Access-Control-Expose-Headers "Authorization"
		Access-Control-Allow-Credentials "true"
	}

	handle @cors_preflight {
		header {
			Access-Control-Allow-Methods "GET, POST, PUT, PATCH, DELETE"
			Access-Control-Max-Age "3600"
		}
		respond "" 204
	}
}

:80 {
  import cors {header.origin}
}