support streaming - Githubissues

I think the most satisfying interface may be, given some selection:

fill in the selection range with empty lines
clear selection
start streaming
fill in lines as they appear in the output
if there are more lines in the output than in the original selection, add them as the streaming continues
if there are fewer lines in the output once the chat is done streaming, delete the empty lines
set the cursor position to the top of the original selection

simonpcouch / pal