fix potential endless loop during queue msg/hook pagination when environment has TZ UTC, triggered by tests introduced in previous test

time.Now() returns a timestamp with timezone Local. if you marshal & unmarshal
it again, it'll get the Local timezone again. unless the local timezone is UTC.
then it will get the UTC timezone. the same time.Time but with explicit UTC
timezone vs explicit UTC-as-Local timezone are not the same when comparing with
==. so comparison should be done with time.Time.Equal, or comparison should be
done after having called .Local() on parsed timestamps (so the explicit UTC
timezone gets converted to the UTC-as-Local timezone). somewhat surprising that
time.Local isn't the same as time.UTC if TZ=/TZ=UTC. there are warnings
throughout the time package about handling of UTC.

develop.txt

@@ -309,7 +309,7 @@ done
 - Update features & roadmap in README.md
 - Write release notes, copy from previous.
 - Build and run tests with previous major Go release.
-- Run tests, including with race detector.
+- Run tests, including with race detector, also with TZ= for UTC-behaviour.
 - Run integration and upgrade tests.
 - Run fuzzing tests for a while.
 - Deploy to test environment. Test the update instructions.

queue/hook.go

@@ -313,9 +313,9 @@ func (s HookSort) apply(q *bstore.Query[Hook]) error {
 		q.FilterNotEqual("ID", s.LastID)
 		var fieldEqual func(h Hook) bool
 		if s.Field == "NextAttempt" {
-			fieldEqual = func(h Hook) bool { return h.NextAttempt == last }
+			fieldEqual = func(h Hook) bool { return h.NextAttempt.Equal(last) }
 		} else {
-			fieldEqual = func(h Hook) bool { return h.Submitted == last }
+			fieldEqual = func(h Hook) bool { return h.Submitted.Equal(last) }
 		}
 		if s.Asc {
 			q.FilterGreaterEqual(s.Field, last)
@@ -454,9 +454,9 @@ func (s HookRetiredSort) apply(q *bstore.Query[HookRetired]) error {
 		q.FilterNotEqual("ID", s.LastID)
 		var fieldEqual func(hr HookRetired) bool
 		if s.Field == "LastActivity" {
-			fieldEqual = func(hr HookRetired) bool { return hr.LastActivity == last }
+			fieldEqual = func(hr HookRetired) bool { return hr.LastActivity.Equal(last) }
 		} else {
-			fieldEqual = func(hr HookRetired) bool { return hr.Submitted == last }
+			fieldEqual = func(hr HookRetired) bool { return hr.Submitted.Equal(last) }
 		}
 		if s.Asc {
 			q.FilterGreaterEqual(s.Field, last)

queue/hook_test.go

@@ -82,6 +82,7 @@ func TestHookIncoming(t *testing.T) {
 		dec := json.NewDecoder(strings.NewReader(h.Payload))
 		err = dec.Decode(&in)
 		tcheck(t, err, "decode incoming webhook")
+		in.Meta.Received = in.Meta.Received.Local() // For TZ UTC.
 
 		expIncoming := webhook.Incoming{
 			From:       []webhook.NameAddress{{Address: "mjl@mox.example"}},

queue/queue.go

@@ -492,9 +492,9 @@ func (s Sort) apply(q *bstore.Query[Msg]) error {
 		q.FilterNotEqual("ID", s.LastID)
 		var fieldEqual func(m Msg) bool
 		if s.Field == "NextAttempt" {
-			fieldEqual = func(m Msg) bool { return m.NextAttempt == last }
+			fieldEqual = func(m Msg) bool { return m.NextAttempt.Equal(last) }
 		} else {
-			fieldEqual = func(m Msg) bool { return m.Queued == last }
+			fieldEqual = func(m Msg) bool { return m.Queued.Equal(last) }
 		}
 		if s.Asc {
 			q.FilterGreaterEqual(s.Field, last)
@@ -1015,9 +1015,9 @@ func (s RetiredSort) apply(q *bstore.Query[MsgRetired]) error {
 		q.FilterNotEqual("ID", s.LastID)
 		var fieldEqual func(m MsgRetired) bool
 		if s.Field == "LastActivity" {
-			fieldEqual = func(m MsgRetired) bool { return m.LastActivity == last }
+			fieldEqual = func(m MsgRetired) bool { return m.LastActivity.Equal(last) }
 		} else {
-			fieldEqual = func(m MsgRetired) bool { return m.Queued == last }
+			fieldEqual = func(m MsgRetired) bool { return m.Queued.Equal(last) }
 		}
 		if s.Asc {
 			q.FilterGreaterEqual(s.Field, last)