[Feature request] Add option to disable easily abusable API easily.

[Fijxu]

Most public instances have to yes or yes, disable the Invidious API to prevent bots and abusers from spamming API endpoints that trigger a video fetch in Invidious companion, most of them (including me) have to disable access to those endpoints using reverse proxy and manual discovery since we do not have a list of the endpoints that an instance owner is recommended to disable for the public.

So because of that it would be great to have a built-in option that let's instance owners and self-hosters to disable the endpoints that can be abused, therefore rate-limiting the instance for legit users using the instance.

Related to: #3032

[Sommerwiesel]

Second this.
A simple api_enabled in the config would be great.

[unixfox]

Sounds like an easy PR to submit. Adding help needed label.