feat(idempotency): return existing record in IdempotencyValidationError

[kevin-secrist]

Description of your changes

Exposes the IdempotencyRecord which failed payload validation as a property on the thrown IdempotencyValidationError.

Related issues, RFCs

Issue number: closes #2048

Checklist

• My changes meet the tenets criteria
• I have performed a self-review of my own code
• I have commented my code where necessary, particularly in areas that should be flagged with a TODO, or hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my change is effective and works
• The PR title follows the conventional commit semantics

Breaking change checklist

Is it a breaking change?: NO

• I have documented the migration process
• I have added, implemented necessary warnings (if it can live side by side)

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[boring-cyborg]

Thanks a lot for your first contribution! Please check out our contributing guidelines and don't hesitate to ask whatever you need.
In the meantime, check out the #typescript channel on our Powertools for AWS Lambda Discord: Invite link

[dreamorosi]

Thank you for opening this PR, looks good to me!

[dreamorosi]

Hi @kevin-secrist, I'm looking at some issues on the integration tests around the Idempotency package.

I don't think they're related to the changes in this PR but just to be safe I'd like to take a bit more time to identify the issue before merging this PR.

[dreamorosi]

I was able to isolate the issue on the integration tests and confirm it's not related to the changes in this PR.

I'm opening another PR to fix them, and once that's merged we'll run the tests once again and merge this.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[dreamorosi]

Integration tests are passing, thank you for the patience: https://github.com/aws-powertools/powertools-lambda-typescript/actions/runs/7930491156

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!