fix(options): mark winhighlight as list style (#19477)

Also add missing fcs, lcs and winhighlight to list of key-value options for `vim.opt`.

Co-authored-by: ii14 <ii14@users.noreply.github.com>

src/nvim/options.lua

@@ -2868,7 +2868,8 @@ return {
     {
       full_name='winhighlight', abbreviation='winhl',
       short_desc=N_("Setup window-local highlights");
-      type='string', scope={'window'},
+      type='string', list='onecomma', scope={'window'},
+      deny_duplicates=true,
       alloced=true,
       redraw={'current_window'},
       defaults={if_true=""}