feat(sinks): introduce RetryStrategy / Config for http based sinks

[ndrsg]

Summary

This PR introduces a configurable retry_strategy for Vector's shared HTTP retry logic and exposes it on the http sink plus the sinks built on the same HTTP retry helpers.

It adds support for default, none, all, and custom retry modes, wires that behavior through the affected HTTP-based sinks, and adds documentation plus test coverage for custom status-code retries. The default strategy now consistently retries 408, 429, and 5xx responses across the shared HTTP retry implementations.

Affected sinks

Configurable sinks using HttpStatusRetryLogic:

• http
• axiom
• opentelemetry
• appsignal
• azure_logs_ingestion
• azure_monitor_logs
• datadog_events
• gcp_stackdriver_logs
• gcp_stackdriver_metrics
• honeycomb
• keep
• prometheus_remote_write

Sinks that still use HttpRetryLogic and are not made configurable by this PR:

• clickhouse
• greptimedb logs
• influxdb_metrics
• sematext_metrics
• splunk_hec logs
• splunk_hec metrics

Vector configuration

I used the new HTTP sink example configuration to validate the custom retry behavior (also checked in in examples folder):

data_dir: "/var/lib/vector"

sources:
  demo_logs:
    type: "demo_logs"
    format: "json"
    interval: 1

sinks:
  http_out:
    type: "http"
    inputs: [ "demo_logs" ]
    uri: "https://example.com/ingest"
    method: "post"

    healthcheck:
      enabled: false

    framing:
      method: "newline_delimited"
    encoding:
      codec: "json"

    request:
      timeout_secs: 60
      retry_attempts: 8
      retry_initial_backoff_secs: 2
      retry_max_duration_secs: 30

    retry_strategy:
      type: "custom"
      status_codes: [ 408, 425, 429, 503 ]

How did you test this PR?

• Added unit coverage for the shared RetryStrategy behavior in src/sinks/util/http.rs.
• Added HTTP sink tests covering both retryable configured status codes and non-retryable unconfigured status codes in src/sinks/http/tests.rs.
• Built the Vector binary locally and validated config/examples/http_sink_custom_retry.yaml against it.
• Ran make check-clippy locally.
• Validated the changelog fragment with ./scripts/check_changelog_fragments.sh.

Change Type

• Bug fix
• New feature
• Dependencies
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the no-changelog label to this PR.

References

• Consider expanding the cases where Vector retries requests #10870

[github-actions]

All contributors have signed the CLA ✍️ ✅
_{Posted by the CLA Assistant Lite bot.}

[ndrsg]

I have read the CLA Document and I hereby sign the CLA

[pront]

@codex review - draw context from #10870 (comment)

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 27feabc878

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[pront]

Will come back to this PR once the open codex comments are resolved (feel free to dispute those if they don't make sense)

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 6b7885db44

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

[ndrsg]

@pront I addressed codex suggestions. The failing spell-check in the workflow does not seem to be related to my changes.

[pront]

@pront I addressed codex suggestions. The failing spell-check in the workflow does not seem to be related to my changes.

Thank you @ndrsgm, you can ignore the spell-check workflow failures. I will take another look at this PR shortly.

[pront]

This looks good for the most part. Thanks!

[ndrsg]

Hello @pront, any news about this PR? I saw that some checks failed so I pushed additional changes for the doc generation.
The workflow assigned the work-in-progress label, but I don't know what that means. From my side there is no work in progress at the moment an I am waiting for the next feedback.

[pront]

Hi @ndrsg, this PR is in great shape. The work in progress label is only for our internal coordination. It is remove once the PR is approved by a maintainer. I will do one final review. I am optimistic that we can include this in the next release.

[pront]

Awesome PR, thanks!