fix(routes): ensure routes are correctly propagated

When using Tailscale v1.34.1, enabling or disabling a route does not
effectively add or remove the route from the node's routing table.
We must restart tailscale on the node to have a netmap update.

Fix this by refreshing last state change so that a netmap diff is sent.

Also do not include secondary routes in allowedIPs, otherwise secondary
routes might be used by nodes instead of the primary route.

Signed-off-by: Fatih Acar <facar@scaleway.com>

routes.go

@@ -215,6 +215,7 @@ func (h *Headscale) handlePrimarySubnetFailover() error {
 		log.Error().Err(err).Msg("error getting routes")
 	}
 
+	routesChanged := false
 	for pos, route := range routes {
 		if route.isExitRoute() {
 			continue
@@ -235,6 +236,7 @@ func (h *Headscale) handlePrimarySubnetFailover() error {
 					return err
 				}
 
+				routesChanged = true
 				continue
 			}
 		}
@@ -306,9 +308,14 @@ func (h *Headscale) handlePrimarySubnetFailover() error {
 
 				return err
 			}
+
+			routesChanged = true
 		}
 	}
 
+	if routesChanged {
+		h.setLastStateChangeToNow()
+	}
 	return nil
 }