Counter for Retry Policies on Envoy Proxy

[msfidelis]

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Describe the feature request
I think the capability to export metrics/counter based on envoy retry policies can be very useful for improve envoy observability. For example, for instance, retry count and condition.

Example on istio_requests_total we have a response_flags tag, we can be enhance this metrics with a retry_count propertie.

Affected product area (please put an X in all that apply)

[ ] Ambient
[ ] Docs
[ ] Dual Stack
[ ] Installation
[x] Networking
[ ] Performance and Scalability
[x] Extensions and Telemetry
[ ] Security
[ ] Test and Release
[ ] User Experience
[ ] Developer Infrastructure

Affected features (please put an X in all that apply)

[ ] Multi Cluster
[ ] Virtual Machine
[ ] Multi Control Plane

Additional context

[zirain]

you can do it yourselft whit Telemetry API or EnvoyFilter, I don't think it should be on by default.

[istio-policy-bot]

🧭 This issue or pull request has been automatically marked as stale because it has not had activity from an Istio team member since 2023-10-25. It will be closed on 2024-05-07 unless an Istio team member takes action. Please see this wiki page for more information. Thank you for your contributions.

Created by the issue and PR lifecycle manager.