fish: Use editor as floaterm inside a neovim floating terminal

Note that this works only in floaterm. Opening a terminal with
:terminal, will not have floaterm available in it.

fish/.config/fish/config.fish

@@ -2,12 +2,19 @@ set PATH {$HOME}/.nix-profile/bin {$HOME}/.cargo/bin {$HOME}/.cabal/bin $PATH
 set -gx TERM xterm-kitty
 set -gx NIX_PATH {$HOME}/.nix-defexpr/channels
 
-export EDITOR='nvim'
 export BROWSER='firefox'
 export MANPAGER='nvim +Man!'
 export NIX_SSL_CERT_FILE='/etc/ssl/certs/ca-certificates.crt'
 export MOZ_ENABLE_WAYLAND=1
 
+if [ -n "$NVIM_LISTEN_ADDRESS" ]
+  export VISUAL="floaterm"
+  export EDITOR="floaterm"
+else
+  export VISUAL="nvim"
+  export EDITOR="nvim"
+end
+
 alias b="cd .."
 alias c="clear"
 alias v="nvim"