patch 8.2.1459: Vim9: declaring script var in script does not infer the type

Problem:    Vim9: declaring ascript variable at the script level does not
            infer the type.
Solution:   Get the type from the value. (closes #6716)

src/evalvars.c

@@ -3049,7 +3049,10 @@ set_var_const(
 						      + si->sn_var_vals.ga_len;
 		sv->sv_name = di->di_key;
 		sv->sv_tv = &di->di_tv;
-		sv->sv_type = type == NULL ? &t_any : type;
+		if (type == NULL)
+		    sv->sv_type = typval2type(tv, &si->sn_type_list);
+		else
+		    sv->sv_type = type;
 		sv->sv_const = (flags & LET_IS_CONST);
 		sv->sv_export = is_export;
 		++si->sn_var_vals.ga_len;

src/testdir/test_vim9_script.vim

@@ -2914,12 +2914,20 @@ def Test_let_declaration()
     let s:other: number
     other = 1234
     g:other_var = other
+
+    # type is inferred
+    s:dict = {'a': 222}
+    def GetDictVal(key: any)
+      g:dict_val = s:dict[key]
+    enddef
+    GetDictVal('a')
   END
   CheckScriptSuccess(lines)
   assert_equal('', g:var_uninit)
   assert_equal('text', g:var_test)
   assert_equal('prefixed', g:var_prefixed)
   assert_equal(1234, g:other_var)
+  assert_equal(222, g:dict_val)
 
   unlet g:var_uninit
   unlet g:var_test

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1459,
 /**/
     1458,
 /**/