refactor(config): remove component base metadata

[pront]

Summary

Previously, SourceOuter carried an extra tag:

"_metadata": {
  "docs::component_base_type": "source"
}

The docs generator searched for that tag to find the shared source configuration.

Now it follows the relationship already in the schema—simplified here:

{
  "properties": {
    "sources": {
      "additionalProperties": {
        "$ref": "#/definitions/SourceOuter"
      }
    }
  }
}

That says: every entry under sources uses SourceOuter. So we can discover the wrapper without separately tagging it.

The same reference also tells the schema generator to preserve that definition instead of inlining it. The same approach applies to sinks and transforms.

No user configuration changes. Same validation and generated docs; one redundant metadata tag removed.

References

Related: #26450. This PR is based directly on master and does not include the coercion changes.

Vector configuration

Not applicable; configuration behavior is unchanged.

How did you test this PR?

• 78 schema/config tests and 12 component-docs tests passed, including new root-map discovery, reference-cycle, and wrapper-preservation regressions.
• Clippy passed for all targets in vector-config-common, vector-config, docs-renderer, and vdev.
• Compared full default-feature schemas before and after the change: identical after removing only the retired metadata from the baseline.
• Regenerated component docs, VRL docs, and examples with the updated local generator; no generated files changed.
• make fmt and git diff --check passed.

Does this PR include user facing changes?

• Yes.
• No. A maintainer will apply the no-changelog label to this PR.

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-22T15:05:31.085081Z	b2b8a31	PR opened
🔒 Security Review	✅ Completed 2026-09-22T15:06:19.324671Z	b2b8a31	PR opened

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