runtime(vim): Update base syntax, match Vim9 object type constructor

fixes: #18677.
closes: #18691

Reported by Aliaksei Budavei.

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

runtime/syntax/testdir/input/vim9_types.vim

@@ -1,7 +1,7 @@
 vim9script
 # Vim9 types
 # VIM_TEST_SETUP hi link vimTypeAny Todo
-# VIM_TEST_SETUP hi link vimVariableTypeAny Todo
+# VIM_TEST_SETUP hi link vim9VariableTypeAny Todo
 
 
 # builtin types (distinct any highlighting)

runtime/syntax/testdir/input/vim9_types_example_object.vim

@@ -0,0 +1,31 @@
+vim9script
+# Vim9 object type constructor
+# VIM_TEST_SETUP hi link vimTypeObject Todo
+# VIM_TEST_SETUP hi link vim9VariableTypeObject Todo
+
+
+# Issue #18677 (No recognition of object<any> types - Aliaksei Budavei)
+
+interface I
+  def string(): string
+endinterface
+
+class C implements I
+  def string(): string
+    return "C"
+  enddef
+endclass
+
+enum E implements I
+  INSTANCE
+
+  def string(): string
+    return "E"
+  enddef
+endenum
+
+var c: object<C> = C.new()
+var e: object<E> = E.INSTANCE
+var os: tuple<object<any>, object<I>> = (c, e)
+echo (c, e) == os
+

runtime/syntax/testdir/input/vim9_types_object.vim

@@ -0,0 +1,27 @@
+vim9script
+# Vim9 object type constructor
+# VIM_TEST_SETUP hi link vimIypeObject Todo
+# VIM_TEST_SETUP hi link vim9VariableIypeObject Todo
+
+
+interface I
+endinterface
+
+var a: object<I>
+var b: object<any>
+var c: object<object<I>>
+var d: object<object<any>>
+
+def Foo(
+    arg1: object<I>,
+    arg2: object<any>,
+    arg3: object<object<I>>,
+    arg4: object<object<any>>)
+enddef
+
+def Bar(): object<I>
+enddef
+
+def Baz(): object<object<I>>
+enddef
+