chore: simplify unfollow function

[kasugamirai]

No description provided.

[reyamir]

In the PR #208 , I've merged follow and unfollow functions into toggle_contact

pub async fn toggle_contact(
  hex: &str,
  alias: Option<&str>,
  state: State<'_, Nostr>,
) -> Result<String, String> {
  let client = &state.client;

  match client.get_contact_list(None).await {
    Ok(mut contact_list) => {
      let public_key = PublicKey::from_str(hex).unwrap();

      match contact_list.iter().position(|x| x.public_key == public_key) {
        Some(index) => {
          // Remove contact
          contact_list.remove(index);
        }
        None => {
          // TODO: Add relay_url
          let new_contact = Contact::new(public_key, None, alias);
          // Add new contact
          contact_list.push(new_contact);
        }
      }

      // Update local state
      state.contact_list.lock().unwrap().clone_from(&contact_list);

      // Publish
      match client.set_contact_list(contact_list).await {
        Ok(event_id) => Ok(event_id.to_string()),
        Err(err) => Err(err.to_string()),
      }
    }
    Err(err) => Err(err.to_string()),
  }
}