proposal for an 'appsocket' protocol

[Jose E. Marchesi]

        Experience with GNU poke [3] has shown that the model (C) provides very
        satisfying user interactions.
    
    For a description of how an experimental version of the protocol
    suggested by Bruno has been exploited in the interactive tool `poke'
    please see:
    
    https://lists.nongnu.org/archive/html/poke-devel/2019-11/msg00034.html

And for a taste on how it feels like to use it, see this little
screencap (recorded by Darshit Shah):

http://www.jemarch.net/images/poke-hyperlinks.mkv

The demo shows two different kind of links:
- One kind executes poke commands without perturbing the prompt.
- The other kind inserts stuff in the prompt at the current position of
  the cursor (we use GNU libreadline as the editor in the repl.)

Of course that distinction is encoded in the payload and therefore
doesn't concern the protocol itself.  It is specific to poke.

I have to say we are very excited with the possibility of implementing
this kind of smooth interaction further in GNU poke, and we really hope
Bruno's proposal gets worked out and eventually standardized.

Salud!