notify/email.go accumulated multi-recipient errors with
multierror.Append(fmt.Errorf(...)) instead of
multierror.Append(result, ...), so the accumulator was overwritten each
iteration and only the last failing recipient's error survived; earlier
failures were silently dropped. The telegram notifier did it correctly.
Replace hashicorp/go-multierror with the stdlib errors.Join everywhere
it was used (notify/email.go, notify/telegram.go, rest/api/rest_private.go,
store/service/service.go, store/image/image.go and store/engine/bolt.go),
which fixes the bug and drops the direct dependency. It stays indirect
because go-pkgz/lcw/v2 still imports it. A regression test in
email_test.go now sends two failing recipients and asserts both errors
are reported.
Dmitry VerkhoturovandUmputun
f8f2becb4b