Display Airy instance version in the Control Center & Inbox UI

[steffh]

Is your feature request related to a problem? Please describe.

As an Airy user of the Control Center & Inbox UI, I cannot see at the moment which version my Airy instance is running and whether there are any updates available

Describe the solution you'd like

1. Display the current version in the product

The POST /client.config route should contain information on the version number of the relevant Airy instance, so that the Control Center UI and the Inbox UI can display that somewhere, so that we can also ask people who report issues which version they are running

2. Optional Extension: Suggest Upgrades because of a (major) new version

Ideally we could make the relevant Airy instance look up if there is a new version of Airy available in the background from time to time, extending the information provided via the POST /client.config route providing the version number of the current version of the Airy instance, so that the Control Center UI and Inbox UI can suggest to upgrade to the newest version for a new (major) release

Additional context

This functionality would be very similar to the airy upgrade command we currently have in the Airy CLI:

[chrismatix]

This has been done