Backport of HCP Telemetry Feature into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #17460 to be assessed for backporting due to the inclusion of the label backport/1.15.

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The person who merged in the original PR is:
@Achooo
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

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The below text is copied from the body of the original PR.

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Description

This is the final PR for the merge of the HCP Telemetry feature branch (feature/hcp-telemetry) into main
A feature branch was used, where the code was thoroughly reviewed in multiple PRs, as seen by the commit history, in order:

1. [HCP Observability] Move HCP client to subpackage hcp/client #16800
2. [HCP Observability] New MetricsClient #17100
3. [HCP Observability] OTELExporter #17128
4. [HCP Observability] OTELSink #17159
5. [HCP Observability] Init OTELSink in Telemetry #17162
6. [HCP Observability] Metrics filtering and Labels in Go Metrics sink #17184
7. [HCP Observability] Remove replica tag #17484
8. [HCP Observability] Add custom metrics for OTEL sink, improve logging, upgrade modules and cleanup metrics client #17455
9. [HCP Observability] Turn off retries for now until dynamically configurable #17496
10. Last commit for changelog

Feature background

RFC: [CSL-267] Export Server Metrics to HCP

The new HCP Observability feature requires sending Consul Server metrics to HCP's new Telemetry Gateway.
The idea is to create a new OpenTelemetry Go Metrics sink that will be initialized automatically within the fanout sink when a Consul server is registered with the HCP management plane.

Testing & Reproduction steps

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 2fdd0e9 - d8927ba - 27753e4 - fb92de5 - 68e6e21 - bb6cfb3 - 3d9fe07 - 8b95718 - bf17ef4 - 1f1d5bd - 1c28984

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[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR