feat: installer fetched from the direct address sets it as the agent's own with the main one as fallback (and downloads from it); agents fall back to whichever address is not theirs; (direct) beside the connection status

internal/agent/wslink.go

@@ -165,7 +165,7 @@ func (a *Agent) runWS(ctx context.Context) error {
 			}
 		case "cfg":
 			a.applyTunnelAddr(ctx, m.Tunnel)
-			a.learnFallback(m.Fallback)
+			a.learnAddrs(m.Main, m.Fallback)
 			a.applyTransport(m.Transport)
 			if a.mode() == proto.TransportLP {
 				return errors.New("set to long polling")