fix(windows): create CJK test root with UTF-8 mkdir

Signed-off-by: Cosm1cAC <cosm1cac@github.com>

Author: Cosm1cAC

tests/test_mcp.c

@@ -1774,7 +1774,10 @@ TEST(search_code_scoped_path_with_cjk_root_issue903) {
     char proj_dir[640];
     snprintf(proj_dir, sizeof(proj_dir), "%s/%s", tmp,
              "\xE4\xB8\xAD\xE6\x96\x87\xE9\xA1\xB9\xE7\x9B\xAE");
-    cbm_mkdir(proj_dir);
+    if (!cbm_mkdir_p(proj_dir, 0755)) {
+        cbm_rmdir(tmp);
+        FAIL("cannot create CJK project dir");
+    }
 
     char src_path[768];
     snprintf(src_path, sizeof(src_path), "%s/main.go", proj_dir);