feat(cfn-include): allow cyclical dependencies

[AlexanderADietrich]

Add an optional flag that both disables throwing an error on cyclical references and utilizes a placeholder->replace->delete method of recursion breaking to avoid stack overflows.

This enables users of cloudformation transforms (example: SAM) to import their unprocessed templates without manual intervention, allowing scale that otherwise is unachievable using current workarounds such as pre-processing or downloading processed templates.

Add a flag to Template within the assertions package to allow uniting of this change.

Fixes https://github.com/aws/aws-cdk/issues/22071

Shoutout to https://github.com/rix0rrr and https://github.com/skinny85 for creation of the new issue/discussions and discussions respectively.

Additionally verified (beyond uniting) by processing template currently broken by lack of circular ref processing and this change successfully allows processing of that template. Cannot share as it is private, and a different scrubbed example has already been provided in fixed issue.

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• Commit ID: 4db8c060b83a17854cce8f5239390aacac303c4c
• Result: SUCCEEDED
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Thank you for contributing! Your pull request will be updated from main and then merged automatically (do not update manually, and be sure to allow changes to be pushed to your fork).