feat: Changes to support external cred in CLI

[tesmarishy]

Pull Request

Summary

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Changes in EnvGene to support management of Credentials that reside in external secret stores.

Issue

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No Github issue.
EnvGene cannot be used in projects where policy prohibits storing secrets in Git, even in encrypted form.
It is necessary to extend EnvGene to support management of Credentials that reside in external secret stores.

Breaking Change?

• Yes
• No

No
If yes, describe the breaking change and its impact (e.g., API changes, behavior changes, or required updates for users).

Scope / Project

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Effective set job.

Implementation Notes

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1. Add mapping support from the new external credential type in credentials.yml to the Credential DTO.
2. Add mapping support for secret stores to the corresponding DTO.
3. Read SECRET_FLOW and eso_support from parameters and use them to determine the reference format:
   o ESO references
   o Vals references
4. Detect parameters using the credRef structure and generate the corresponding ESO or Vals reference.
5. Populate these generated references into external-credentials.yml under the deployment context.
6. Populate external-credentials.yml under the external-credential context with:
   o Credentials where create: true
   o Their associated secret stores

Tests / Evidence

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Testing done in instance pipeline.

• Tests added or updated (e.g., unit, integration, end-to-end)
• Manual testing steps or results
• Screenshots, logs, or other evidence (if applicable)

Additional Notes

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• Dependencies introduced
• Future work or follow-up tasks
• Reviewer instructions or context
• References to related PRs or discussions

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