Cache control HTTP headers (json)

Implementation	bifrost-gateway	boxo	kubo
Conformance Version	main	main	main
Total	✅4	✅4	✅4
Header Cache-Control	✅1	✅1	✅1
Header Etag	✅1	✅1	✅1
Header X-Ipfs-Path	✅1	✅1	✅1
Header X-Ipfs-Roots	✅1	✅1	✅1