Fix that live-query system sometimes does not send the changed result-set to the frontend

[Venryx]

Copied notes:

Also, I have replicated the problem with the "notifications" subscription sometimes not sending changes to the user: In my case, it happens if I clear the notifications table, load the page, then insert a notification entry for the user; the notification(s) do not start getting picked up on (by the client) until I refresh the page.

What's weird is that I've inspected the live-query system's internals (there's a page at localhost:5100/monitor/db/watchers for this, after entering the admin-key [the password of the pguser-admin... secret in k8s for now] on the monitor tool's homepage), and the live-query system is correctly noticing the new notifications and updating the live-query state. But for some reason it is not sending them to the user. So investigating this will be my next task.

[Venryx]

Might be due to not doing the subscription through mobx-graphlink atm, so sub doesn't get recreated after auth data being attached to websocket, so RLS rules are just filtering out the results.

[Venryx]

My guess in the comment above was correct; it was just a side-effect of not having the subscription managed by mobx-graphlink (ie. re-requesting the subscription after auth-data was attached to the websocket connection). For more details, see the commit here that fixes the issue: 97afa9c