This is to prepare for an upcoming change where we will need to track
replies to messages by ID. We will be able to add parameters to this
structure without having to edit every single actor subclass header
file.
To aid with debugging web page issues in Ladybird without needing to
implement a fully fledged inspector, we can implement the Firefox
DevTools protocol and use their DevTools. The protocol is described
here:
https://firefox-source-docs.mozilla.org/devtools/backend/protocol.html
This commit contains just enough to connect to Ladybird from a DevTools
client.
