runtime(vim): Update base syntax, match "any" type distinctly

Allow for special highlighting of the "any" Vim9 type.

Addresses comment
https://github.com/vim/vim/pull/17722#issuecomment-3075531052

closes: #17769

Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/syntax/testdir/input/vim9_types.vim

@@ -0,0 +1,17 @@
+vim9script
+# Vim9 types
+# VIM_TEST_SETUP hi link vimTypeAny Todo
+# VIM_TEST_SETUP hi link vimVariableTypeAny Todo
+
+
+# builtin types (distinct any highlighting)
+
+var foo: bool
+var bar: any
+
+def Foo(arg: bool): bool
+enddef
+
+def Bar(arg: any): any
+enddef
+