all the changes

internal/collector/collector_test.go

@@ -392,6 +392,47 @@ func TestHandleIssuesAndByID(t *testing.T) {
 	}
 }
 
+func TestIssueTrendsUseTelemetryTimestamps(t *testing.T) {
+	coll := New(noopBroadcaster{}, 10, nil)
+
+	base := time.Date(2026, 9, 19, 10, 0, 0, 0, time.UTC)
+	ld := plog.NewLogs()
+	rl := ld.ResourceLogs().AppendEmpty()
+	rl.Resource().Attributes().PutStr("service.name", "api")
+	records := rl.ScopeLogs().AppendEmpty().LogRecords()
+	first := records.AppendEmpty()
+	first.SetTimestamp(pcommon.NewTimestampFromTime(base))
+	first.SetSeverityNumber(plog.SeverityNumberError)
+	first.Body().SetStr("first failure")
+	second := records.AppendEmpty()
+	second.SetTimestamp(pcommon.NewTimestampFromTime(base.Add(time.Hour)))
+	second.SetSeverityNumber(plog.SeverityNumberError)
+	second.Body().SetStr("second failure")
+
+	if err := coll.ConsumeLogs(context.Background(), ld); err != nil {
+		t.Fatalf("ConsumeLogs failed: %v", err)
+	}
+
+	list := coll.ListIssues(0)
+	if len(list) != 2 {
+		t.Fatalf("expected two issues, got %d", len(list))
+	}
+	for _, issue := range list {
+		if len(issue.Trend) != 1 {
+			t.Fatalf("expected one trend bucket for %q, got %+v", issue.Title, issue.Trend)
+		}
+	}
+	expected := map[string]string{
+		"first failure":  issues.HourBucket(base.UnixNano()),
+		"second failure": issues.HourBucket(base.Add(time.Hour).UnixNano()),
+	}
+	for _, issue := range list {
+		if _, ok := issue.Trend[expected[issue.Title]]; !ok {
+			t.Fatalf("telemetry timestamp was not used for %q: %+v", issue.Title, issue.Trend)
+		}
+	}
+}
+
 func TestHandleMLDetectorTest(t *testing.T) {
 	coll := New(nil, 10, nil)
 	req := httptest.NewRequest(http.MethodPost, "/api/ml/test-spike", nil)