[enhancement] Implement NIP-78

[tincho70]

Implement NIP-78 to store configuration data like List of relays in NOSTR.

Proposal

User with pubkey XXXXX has 3 relays configured: nos.lol and relay.lawallet.ar connected, but relay.damus.io disconnected

{
  "created_at": 1714006712,
  "content": "",
  "tags": [
    ["d", "nostr-debugger"],
    ["r", "wss://nos.lol", true],
    ["r", "wss://relay.damus.io", false],
    ["r", "wss://relay.lawallet.ar", true],
  ],
  "kind": 30078,
  "pubkey": "XXXXX",
  [...]
}