Reformat new test files with Stroustrup style

Apply emacs CC-mode "stroustrup" style (c-basic-offset 4, indent-tabs-mode t)
to the test files added in the previous commit, matching the existing house
style. Whitespace only; no behavioral change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/err_handle_group.c

@@ -26,7 +26,7 @@ akerr_ErrorContext *run(int status)
     } CLEANUP {
     } PROCESS(e) {
     } HANDLE(e, AKERR_KEY)
-      HANDLE_GROUP(e, AKERR_INDEX) {
+	  HANDLE_GROUP(e, AKERR_INDEX) {
 	group_fired++;
     } HANDLE(e, AKERR_IO) {
 	other_fired++;