chore(tag_cardinality_limit transform): Add multi-value metric tag support to the tag_cardinality_limit transform

[fuchsnj]

ref: #14742

This adds muti-value tag support. After some discussions with @bruceg, we decided to only implement one of the 3 modes discussed in the RFC, potentially expanding it in the future. The mode implemented treats a single "value" (as counted towards the cardinality limit) as the unique set of values on a tag.

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Regression Test Results

Run ID: c74b192a-62fd-465e-860f-330fbfe817cd
Baseline: a95b755
Comparison: 3cafc85
Total vector CPUs: 7

Explanation

A regression test is an integrated performance test for vector in a repeatable rig, with varying configuration for vector. What follows is a statistical summary of a brief vector run for each configuration across SHAs given above. The goal of these tests are to determine, quickly, if vector performance is changed and to what degree by a pull request. Where appropriate units are scaled per-core.

The table below, if present, lists those experiments that have experienced a statistically significant change in their bytes_written_per_cpu_second performance between baseline and comparision SHAs, with 90.0% confidence OR have been detected as newly erratic. Negative values mean that baseline is faster, positive comparison. Results that do not exhibit more than a ±5% change in mean bytes_written_per_cpu_second are discarded. An experiment is erratic if its coefficient of variation is greater than 0.1. The abbreviated table will be omitted if no interesting changes are observed.

No interesting changes in bytes_written_per_cpu_second with confidence ≥ 90.00% and absolute Δ mean >= ±5%.

Fine details of change detection per experiment.

experiment	Δ mean	Δ mean %	confidence	baseline mean	baseline stdev	baseline stderr	baseline outlier %	baseline CoV	comparison mean	comparison stdev	comparison stderr	comparison outlier %	comparison CoV	erratic	declared erratic
syslog_splunk_hec_logs	215.43KiB/CPU-s	2.44	100.00%	8.61MiB/CPU-s	202.51KiB/CPU-s	2.61KiB/CPU-s	0.0	0.022975	8.82MiB/CPU-s	189.93KiB/CPU-s	2.45KiB/CPU-s	0.0	0.021033	False	False
syslog_humio_logs	204.77KiB/CPU-s	2.3	100.00%	8.68MiB/CPU-s	213.07KiB/CPU-s	2.75KiB/CPU-s	0.0	0.023977	8.88MiB/CPU-s	118.76KiB/CPU-s	1.53KiB/CPU-s	0.0	0.013063	False	False
syslog_regex_logs2metric_ddmetrics	63.21KiB/CPU-s	1.7	100.00%	3.64MiB/CPU-s	374.95KiB/CPU-s	4.84KiB/CPU-s	0.0	0.100547	3.7MiB/CPU-s	398.79KiB/CPU-s	5.15KiB/CPU-s	0.0	0.105159	True	False
datadog_agent_remap_datadog_logs	567.53KiB/CPU-s	1.67	100.00%	33.19MiB/CPU-s	1.22MiB/CPU-s	16.11KiB/CPU-s	0.0	0.036736	33.75MiB/CPU-s	1.13MiB/CPU-s	14.94KiB/CPU-s	0.0	0.033508	False	False
datadog_agent_remap_datadog_logs_acks	563.24KiB/CPU-s	1.66	100.00%	33.07MiB/CPU-s	943.81KiB/CPU-s	12.18KiB/CPU-s	0.0	0.027872	33.62MiB/CPU-s	874.48KiB/CPU-s	11.29KiB/CPU-s	0.0	0.025401	False	False
datadog_agent_remap_blackhole_acks	340.81KiB/CPU-s	1.07	100.00%	31.15MiB/CPU-s	1.53MiB/CPU-s	20.21KiB/CPU-s	0.0	0.049037	31.48MiB/CPU-s	1.09MiB/CPU-s	14.39KiB/CPU-s	0.0	0.034577	False	False
http_to_http_acks	42.4KiB/CPU-s	0.78	57.15%	5.28MiB/CPU-s	2.86MiB/CPU-s	37.78KiB/CPU-s	0.0	0.541497	5.32MiB/CPU-s	2.87MiB/CPU-s	37.95KiB/CPU-s	0.0	0.53971	True	False
splunk_hec_route_s3	74.37KiB/CPU-s	0.62	100.00%	11.64MiB/CPU-s	570.31KiB/CPU-s	7.36KiB/CPU-s	0.0	0.047852	11.71MiB/CPU-s	528.39KiB/CPU-s	6.82KiB/CPU-s	0.0	0.04406	False	False
syslog_log2metric_splunk_hec_metrics	54.23KiB/CPU-s	0.59	100.00%	9.02MiB/CPU-s	245.02KiB/CPU-s	3.16KiB/CPU-s	0.0	0.026527	9.07MiB/CPU-s	273.88KiB/CPU-s	3.54KiB/CPU-s	0.0	0.029479	False	False
otlp_grpc_to_blackhole	2.69KiB/CPU-s	0.28	99.97%	956.69KiB/CPU-s	34.54KiB/CPU-s	456.53B/CPU-s	0.0	0.036097	959.38KiB/CPU-s	46.57KiB/CPU-s	615.22B/CPU-s	0.0	0.048533	False	False
splunk_hec_to_splunk_hec_logs_noack	4.58KiB/CPU-s	0.03	77.06%	13.62MiB/CPU-s	224.96KiB/CPU-s	2.9KiB/CPU-s	0.0	0.016128	13.63MiB/CPU-s	191.52KiB/CPU-s	2.47KiB/CPU-s	0.0	0.013726	False	False
enterprise_http_to_http	2.15KiB/CPU-s	0.02	37.16%	13.62MiB/CPU-s	258.13KiB/CPU-s	3.33KiB/CPU-s	0.0	0.018509	13.62MiB/CPU-s	228.61KiB/CPU-s	2.95KiB/CPU-s	0.0	0.01639	False	False
splunk_hec_indexer_ack_blackhole	-643.51B/CPU-s	-0.0	10.93%	13.62MiB/CPU-s	248.73KiB/CPU-s	3.21KiB/CPU-s	0.0	0.017837	13.62MiB/CPU-s	252.59KiB/CPU-s	3.26KiB/CPU-s	0.0	0.018114	False	False
http_to_http_noack	-254.14B/CPU-s	-0.0	3.49%	13.61MiB/CPU-s	310.0KiB/CPU-s	4.0KiB/CPU-s	0.0	0.022235	13.61MiB/CPU-s	311.58KiB/CPU-s	4.02KiB/CPU-s	0.0	0.022349	False	False
fluent_elasticsearch	435.01B/CPU-s	0.0	56.76%	45.41MiB/CPU-s	30.08KiB/CPU-s	393.04B/CPU-s	0.0	0.000647	45.41MiB/CPU-s	29.87KiB/CPU-s	390.48B/CPU-s	0.0	0.000642	False	False
file_to_blackhole	-1.29KiB/CPU-s	-0.0	5.09%	54.5MiB/CPU-s	1.05MiB/CPU-s	13.83KiB/CPU-s	0.0	0.019218	54.49MiB/CPU-s	1.12MiB/CPU-s	14.78KiB/CPU-s	0.0	0.020538	False	False
splunk_hec_to_splunk_hec_logs_acks	-2.18KiB/CPU-s	-0.02	27.33%	13.62MiB/CPU-s	332.33KiB/CPU-s	4.29KiB/CPU-s	0.0	0.02383	13.62MiB/CPU-s	350.96KiB/CPU-s	4.53KiB/CPU-s	0.0	0.025169	False	False
http_to_http_json	-10.61KiB/CPU-s	-0.08	98.00%	13.61MiB/CPU-s	234.49KiB/CPU-s	3.02KiB/CPU-s	0.0	0.016819	13.6MiB/CPU-s	264.56KiB/CPU-s	3.41KiB/CPU-s	0.0	0.018991	False	False
http_pipelines_blackhole	-2.38KiB/CPU-s	-0.09	82.71%	2.56MiB/CPU-s	117.3KiB/CPU-s	1.51KiB/CPU-s	0.0	0.044799	2.55MiB/CPU-s	67.99KiB/CPU-s	898.67B/CPU-s	0.0	0.025991	False	False
socket_to_socket_blackhole	-12.78KiB/CPU-s	-0.1	99.84%	12.58MiB/CPU-s	289.78KiB/CPU-s	3.74KiB/CPU-s	0.0	0.022495	12.57MiB/CPU-s	119.36KiB/CPU-s	1.54KiB/CPU-s	0.0	0.009275	False	False
syslog_log2metric_humio_metrics	-13.21KiB/CPU-s	-0.22	99.98%	5.92MiB/CPU-s	160.26KiB/CPU-s	2.07KiB/CPU-s	0.0	0.026421	5.91MiB/CPU-s	219.23KiB/CPU-s	2.83KiB/CPU-s	0.0	0.036221	False	False
syslog_loki	-18.94KiB/CPU-s	-0.23	100.00%	8.21MiB/CPU-s	163.74KiB/CPU-s	2.11KiB/CPU-s	0.0	0.019464	8.2MiB/CPU-s	310.4KiB/CPU-s	4.01KiB/CPU-s	0.0	0.036983	False	False
http_pipelines_no_grok_blackhole	-47.05KiB/CPU-s	-0.7	100.00%	6.52MiB/CPU-s	76.57KiB/CPU-s	1012.26B/CPU-s	0.0	0.011465	6.48MiB/CPU-s	169.96KiB/CPU-s	2.19KiB/CPU-s	0.0	0.025629	False	False
http_pipelines_blackhole_acks	-19.04KiB/CPU-s	-0.98	100.00%	1.89MiB/CPU-s	47.67KiB/CPU-s	630.45B/CPU-s	0.0	0.024593	1.87MiB/CPU-s	54.33KiB/CPU-s	718.17B/CPU-s	0.0	0.028307	False	False
datadog_agent_remap_blackhole	-318.3KiB/CPU-s	-1.0	100.00%	31.18MiB/CPU-s	849.5KiB/CPU-s	10.97KiB/CPU-s	0.0	0.026608	30.86MiB/CPU-s	1.17MiB/CPU-s	15.41KiB/CPU-s	0.0	0.037771	False	False
http_text_to_http_json	-401.76KiB/CPU-s	-1.63	100.00%	24.03MiB/CPU-s	542.68KiB/CPU-s	7.01KiB/CPU-s	0.0	0.02205	23.64MiB/CPU-s	550.31KiB/CPU-s	7.1KiB/CPU-s	0.0	0.022731	False	False
otlp_http_to_blackhole	-26.72KiB/CPU-s	-1.83	100.00%	1.42MiB/CPU-s	140.77KiB/CPU-s	1.82KiB/CPU-s	0.0	0.096489	1.4MiB/CPU-s	147.04KiB/CPU-s	1.9KiB/CPU-s	0.0	0.102671	True	False