shell: Slim version for "fullscreen" mode (for VNC and third party apps)

[garrett]

Related to

• Quick and easy third party integration points #16964
• Please add full screen option for VNC cockpit-machines#680
• Ability to add/edit/remove consoles cockpit-machines#553 (comment)
• Please add full screen option for VNC cockpit-machines#680

We should have a slimmer version of the shell, where an app can request a smaller version. This would be useful for detail pages that need more screen space, such as the VNC viewer in apps.

Screenshot of mockup @ https://garrett.github.io/cockpit-mockweb/navigation2/fullscreen.html:

[kartikvirendrar]

Hello @garrett, I would like to work on this issue can I get some more details

[garrett]

@kartikvirendrar: Nice!

All the design details are already included here.

I don't know what it would take, except that it would require the shell to have this smaller version and there would need to be some API from the page inside the iframe to communicate to the shell so that the shell would switch modes.

The mode would:

1. hide the navigation on the side
2. add a back link at the top

You'll have to talk to someone else via IRC (during standard European hours) about how the shell works. @martinpitt and @jelly are probably both good people to ask about it.