Add ability to prove IPNS content ownership with libp2p-key

[bbondy]

Placeholder for integrating with rewards for IPFS.

• If a website is opened via DNSLink, use their domain info to allow tips to that creator's content.
• Allow users to "prove" they own certain IPNS content using their libp2p-key. They would basically add content they own and prove they own it in the creators site.

[bbondy]

@lidel do you have an idea on how this could be implemented? Maybe first manually how it could work via command line?

[lidel]

DNSLink is easy – if user already gets credited for https://example.com, Brave should do the same for ipns://example.com

The second one, assuming IPNS is used for publishing as drafted in #14770 (comment), Brave could read user's keys via ipfs key list -l, a command that lists private key names along with pubkey address used in IPNS.

This should be enough to "prove" they are publishers, Brave could also include some unique /.well-known/../file inside the published website as additional check.

[lidel]

ipfs/kubo#10230 will make signing arbitrary bytes with IPNS key easier (removing the need for exporting the key and signing with external code).

It could be used for prooving IPNS key ownership, and/or having a signed pointer to the latest version inside an immutable snapshot of a website.

[lidel]

ipfs key sign|verify RPC commands are in Kubo 0.25.0-rc1 and will be shipped in 0.25 (release notes)

This allows confirming key ownership in offline mode, without having to do online IPNS publishing and resolution dance.