runtime(vim): Update base-syntax, match Vim9 boolean and null literals in parens

- Match Vim9 boolean and null literals in parenthesised expressions and
  function argument lists.
- Match read-only registers in expressions.

closes: #16622

Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index 854e3e0..0d4082a 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -2,7 +2,7 @@
 " Language:	   Vim script
 " Maintainer:	   Hirohito Higashi <h.east.727 ATMARK gmail.com>
 "	   Doug Kearns <dougkearns@gmail.com>
-" Last Change:	   2025 Feb 08
+" Last Change:	   2025 Feb 13
 " Former Maintainer: Charles E. Campbell
 
 " DO NOT CHANGE DIRECTLY.
@@ -298,7 +298,7 @@
 " ====
 syn match vimCall	"\<call\=\>"	skipwhite nextgroup=vimFunc
 
-" Debuggready {{{2
+" Debuggreedy {{{2
 " ===========
 " TODO: special-cased until generalised range/count support is implemented
 syn match	vimDebuggreedy	"\<0\=debugg\%[reedy]\>" contains=vimCount
@@ -343,7 +343,7 @@
 
 " Operators: {{{2
 " =========
-syn cluster	vimOperGroup	contains=@vimSpecialVar,vimFunc,vimLambda,vimOper,vimOperParen,vimNumber,vimString,vimRegister,@vimContinue,vim9Comment,vimVar,vimBoolean,vim9LambdaParams,vimNull
+syn cluster	vimOperGroup	contains=@vimContinue,@vimExprList,vim9Comment
 syn match	vimOper	"\a\@<!!"			skipwhite skipnl nextgroup=@vimOperContinue,@vimExprList,vimSpecFile
 syn match	vimOper	"||\|&&\|[-+*/%.]"		skipwhite skipnl nextgroup=@vimOperContinue,@vimExprList,vimSpecFile
 syn match	vimOper	"?"			skipwhite skipnl nextgroup=@vimOperContinue,@vimExprList
@@ -743,7 +743,7 @@
 syn match	vimRegister	'\<normal\s\+\zs"[a-zA-Z0-9]'
 syn match	vimRegister	'@"'
 syn match	vimPlainRegister contained	'"[a-zA-Z0-9\-:.%#*+=]'
-syn match	vimLetRegister	contained	'@["0-9\-a-zA-Z#=*+_/]'
+syn match	vimLetRegister	contained	'@["0-9\-a-zA-Z:.%#=*+~_/]'
 
 syn match	vimAddress	",\zs[.$]"	skipwhite nextgroup=vimSubst1
 syn match	vimAddress	"%\ze\a"	skipwhite nextgroup=vimString,vimSubst1