Disable embedding when Embed Links permission is denied
Currently all messages have the embed url processor spawned. This should be easy enough, by adding a permissions fetch and disabling the task being spawned if embed_links
is false.
This involves more calculations while writing or editing messages, though. We could add the check just to process_url_embed
in a way that it just returns if the permission is invalid, but we also need to give it more context about the message (especially author id)...