feat(VpcV2): add BYOIP IPv6 to VPCv2

[shikha372]

Issue # (if applicable)

Closes #.

Reason for this change

This PR adds new fields under VPCv2 construct to add BYOIP using AWS pool id and CIDR range of the IPv6 address.

Description of changes

Describe any new or updated permissions being added

No update to permissions.

Description of how you validated changes

Added unit test and integration test.
To test these changes in future, users will need to modify the pool-id with the one hosted in their account and run integration test.
For internal testing, instructions added to team-internal docs with pool onboarding details.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[aws-cdk-automation]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.40%. Comparing base (8e9d7a0) to head (610875b).
Report is 1 commits behind head on main.

Additional details and impacted files

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##             main   #32927   +/-   ##
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  Coverage   81.40%   81.40%           
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  Files         223      223           
  Lines       13727    13727           
  Branches     2411     2411           
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  Hits        11175    11175           
  Misses       2274     2274           
  Partials      278      278           

Flag	Coverage Δ
suite.unit	81.40% <ø> (ø)

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Components	Coverage Δ
packages/aws-cdk	80.74% <ø> (ø)
packages/aws-cdk-lib/core	82.10% <ø> (ø)

✅ Updated pull request passes all PRLinter validations. Dismissing previous PRLinter review.