Support fastly edge

[pi0]

• https://developer.fastly.com/learning/compute/javascript
• https://github.com/fastly/js-compute-runtime

Related: WinterTC55/runtime-keys#6

[pi0]

Moving to the unified tracker: #2973

• Please upvote 👍🏼 this (closed) issue to support
• Please comment here if you would like to work on it