This adds a `-wizard` CLI option to the Manager, which opens a webbrowser
and shows the First-Time Wizard to aid in configuration of Flamenco.
This is work in progress. The wizard is just one page, and doesn't save
anything yet to the configuration.
Vue Router generates URLs for which there are no static files on the
filesystem (like `/jobs/{job ID}`). To make this work, the webapp's
`index.html` has to be served for such requests. The client-side JavaScript
then figures out how things fit together, and can even render a nice 404
page if necessary.
This shouldn't happen for non-webapp URLs, though. Because of this, the
entire webapp (including the "serve `index.html` if file not found logic)
is moved to a `/app/` base URL.
`make flamenco-manager` now also builds the webapp and embeds the static
files into the binary.
`make flamenco-manager_race` does NOT rebuild the static web files, to
help speed up of debug cycles. Run `make webapp-static` to rebuild the
webapp itself, if necessary, or run a separate web development server with
`yarn --cwd web/app run dev --host`.