neovim: change textwidth in line-limiter

it should be less than colorcolumn by 1

neovim/dev.nix

@@ -11,7 +11,7 @@ let
         inherit pattern;
         opt = {
           colorcolumn = toString limit;
-          textwidth = limit;
+          textwidth = limit - 1;
         };
       };
 in
@@ -23,12 +23,9 @@ in
 
   vim.opt = {
     list = true;
-    formatexpr = "neoformat#Neoformat(0, '', v:lnum, v:lnum + v:count)";
   };
 
-  buffer.filetype = {
-    nix.opt.formatexpr = "neoformat#Neoformat(0, '', 0, 99999)";
-  } // lib.listToAttrs [
+  buffer.filetype = lib.listToAttrs [
     (mkLineLimiterGroup {
       limit = 101;
       pattern = [