--watch works differently when used with --server

[lury]

when you run spress site:generate --watch spress is doing good job watching filesystem for changes and regenerating site on the fly, but when you run it with --server like spress site:generate --watch --server regeneration is triggered only when you request (any) page via this internal webserver - i think it should have it's own separate process not connected to webserver.

It's not a big issue since without --server it works fine - just wanted to report it.