Add documentation on how to run graphical applications

### Description

Currently lima has information on how to run a command-line application.

Either using the `nerdctl.lima` wrapper, or starting it from the `lima` shell.

But there is no example on how to run a GUI app, for instance over X11 ?

This can be done both in the QEMU display, or remotely over SSH shell.

1) Typical local qemu DISPLAY: `:0` (from `startx`)

2) Typical remote host DISPLAY: `localhost:10.0` (from `ssh -X`)

Both approaches require some setup of the VM, and some added docs.

See discussion:
* https://github.com/lima-vm/lima/discussions/987

Boot2Docker X11:
* https://gist.github.com/afbjorklund/cb63251c43f73a4314ada904ae8f8d87 (2017)

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Preferrably, this should link to more generic documentation for containers.

For instance, accessing the applications with `x11docker --backend=nerdctl`.

The VM doesn't have so many "secrets" to leak, but the host X11 (alt 2) might

There is lots of detailed info available at: https://github.com/mviereck/x11docker

This command (x11docker) provides improved security, over the more naive approach:

https://github.com/mviereck/x11docker/wiki/Short-setups-to-provide-X-display-to-container