Epic: Automate and Streamline SDK Release Process with CI Pipeline Enhancements

## Summary

The current release process for SDK packages requires a manual trigger of the release pipeline when an SDK is ready to be released, which can be confusing for service partner teams. The CI pipeline is triggered automatically when an SDK pull request is merged, but it does not trigger the release stage. The goal is to enhance the release process by automating checks and enabling the release stage within the CI pipeline when conditions are met.

## Proposal

- Enhance the CI pipeline to automatically check if a package is ready for release after a PR merge:
- Package must have its version updated in the changelog, and the changelog must include a release date
- No existing release tag for the current package and version
- API view approval status and package name approval status must be met
- If all validations pass, set a variable to enable the release stage within the pipeline
- Only packages meeting the validation criteria should proceed to the release stage (even if the pipeline supports multiple packages)
- SDK owner must still manually approve the release in the CI pipeline before the package is published
- Update the common release pipeline template to add these validations
- Change the release stage template to use runtime variables to decide stage execution (not just pre-runtime logic)

## Impact

- Removes the need for manual pipeline triggers by service partner teams
- Reduces confusion and streamlines the release process
- Ensures only validated and approved packages are released

## Tasks
- Update common release pipeline template with validation logic
- Introduce variables to control release stage and package list
- Refactor release stage template to support runtime variable-based logic
- Document new process and required approvals

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This epic will track all related sub-issues required to implement and roll out this improvement.