I updated it to expose `Webapps` function on `client`. So that listTabs isn't changed.
I haven't exposed `listApps` as you can't have a 1-1 equivalent of listTabs for apps.
We can't create actors for all running apps, as it would start injecting stuff in all app processes on listApps call. Instead you have to first figure out which app you want to debug and manually request the Tab object via `webapps.getApp`.

I addressed other review comments.