feat: say what this is all about

[jidanni]

Feature description

1. Website doesn't say what this is all for / does.
2. GitHub Readme: Same problem: https://github.com/orgs/ReVanced/discussions/1419

Motivation

Say what this is all actually for. Not only that it is built on top of something else, or can do something better, without saying what that something is.

Acknowledgements

• I have checked all open and closed feature requests and this is not a duplicate
• I have chosen an appropriate title.
• All requested information has been provided properly.

[oSumAtrIX]

Very fair, we had thought about this, but it's hard to find a good description.