additional account relay list improvements

- Use the current selected account only to determine desired
  relays. Previously the desired relay list was determined from the
  union of all accounts.
- Update the relay configuration immediately when the user switches accounts.
- Delete relays from the account (instead of the relay pool
  directly). This results in the relay being removed in the pool as
  well, but is persisted correctly.

crates/notedeck_columns/src/accounts/mod.rs

@@ -97,7 +97,7 @@ pub fn process_accounts_view_response(
             router.route_to(Route::add_account());
         }
     }
-
+    accounts.needs_relay_config();
     selection
 }