feat(lsp): support textDocument/inlineCompletion

src/gen/gen_vimdoc.lua

@@ -283,6 +283,7 @@ local config = {
       'folding_range.lua',
       'handlers.lua',
       'inlay_hint.lua',
+      'inline_completion.lua',
       'linked_editing_range.lua',
       'log.lua',
       'rpc.lua',

src/nvim/highlight_group.c

@@ -175,6 +175,8 @@ static const char *highlight_init_both[] = {
   "default link PmenuKindSel     PmenuSel",
   "default link PmenuSbar        Pmenu",
   "default link ComplMatchIns    NONE",
+  "default link ComplHint        NonText",
+  "default link ComplHintMore    MoreMsg",
   "default link Substitute       Search",
   "default link StatusLineTerm   StatusLine",
   "default link StatusLineTermNC StatusLineNC",