feat: Neovim v0.11+ configure messagesopt to hide enter prompts on startup

[mikesmithgh]

New option on nightly available: https://neovim.io/doc/user/options.html#'messagesopt'

'messagesopt' 'mopt' string (default "hit-enter,history:500")
global
Option settings for outputting messages. It can consist of the
following items. Items must be separated by a comma.
hit-enter Use a hit-enter prompt when the message is longer than
'cmdheight' size.
wait:{n} Instead of using a hit-enter prompt, simply wait for
{n} milliseconds so that the user has a chance to read
the message. The maximum value of {n} is 10000. Use
0 to disable the wait (but then the user may miss an
important message).
This item is ignored when "hit-enter" is present, but
required when "hit-enter" is not present.
history:{n} Determines how many entries are remembered in the
:messages history. The maximum value is 10000.
Setting it to zero clears the message history.
This item must always be present.