Add fine-grained checkpointing metrics to DRT clusters

We added fine grained checkpointing for changefeeds
in release 25.2. In order to monitor the additional
resources involved in taking the checkpoints, we
added metrics on the total number of bytes, spans,
timestamps and write time involved in these checkpoints.
This commit makes those visible in datadog for DRT
clusters.

Epic: none

Release note: None

Author: aerfrei

pkg/roachprod/opentelemetry/cockroachdb_metrics.go

@@ -333,11 +333,24 @@ var cockroachdbMetrics = map[string]string{
 	"changefeed_buffer_pushback_nanos_aggregator":                         "changefeed.buffer_pushback_nanos.aggregator",
 	"changefeed_buffer_pushback_nanos_rangefeed":                          "changefeed.buffer_pushback_nanos.rangefeed",
 	"changefeed_bytes_messages_pushback_nanos":                            "changefeed.bytes.messages_pushback",
+	"changefeed_checkpoint_create_nanos":                                  "changefeed.checkpoint.create_nanos",
+	"changefeed_checkpoint_create_nanos_bucket":                           "changefeed.checkpoint.create_nanos.bucket",
+	"changefeed_checkpoint_create_nanos_count":                            "changefeed.checkpoint.create_nanos.count",
+	"changefeed_checkpoint_create_nanos_sum":                              "changefeed.checkpoint.create_nanos.sum",
 	"changefeed_checkpoint_hist_nanos":                                    "changefeed.checkpoint_hist",
 	"changefeed_checkpoint_hist_nanos_bucket":                             "changefeed.checkpoint_hist_nanos.bucket",
 	"changefeed_checkpoint_hist_nanos_count":                              "changefeed.checkpoint_hist_nanos.count",
 	"changefeed_checkpoint_hist_nanos_sum":                                "changefeed.checkpoint_hist_nanos.sum",
 	"changefeed_checkpoint_progress":                                      "changefeed.checkpoint_progress",
+	"changefeed_checkpoint_total_bytes":                                   "changefeed.checkpoint.total_bytes",
+	"changefeed_checkpoint_timestamp_count":                               "changefeed.checkpoint.timestamp_count",
+	"changefeed_checkpoint_timestamp_count_bucket":                        "changefeed.checkpoint.timestamp_count.bucket",
+	"changefeed_checkpoint_timestamp_count_count":                         "changefeed.checkpoint.timestamp_count.count",
+	"changefeed_checkpoint_timestamp_count_sum":                           "changefeed.checkpoint.timestamp_count.sum",
+	"changefeed_checkpoint_span_count":                                    "changefeed.checkpoint.span_count",
+	"changefeed_checkpoint_span_count_bucket":                             "changefeed.checkpoint.span_count.bucket",
+	"changefeed_checkpoint_span_count_count":                              "changefeed.checkpoint.span_count.count",
+	"changefeed_checkpoint_span_count_sum":                                "changefeed.checkpoint.span_count.sum",
 	"changefeed_cloudstorage_buffered_bytes":                              "changefeed.cloudstorage_buffered_bytes",
 	"changefeed_commit_latency":                                           "changefeed.commit.latency",
 	"changefeed_commit_latency_bucket":                                    "changefeed.commit_latency.bucket",