feat(mediapackagev2): add region attribute on mediapackagev2 resources and extra naming validation

[jamiepmullan]

Reason for this change

Allow cross-region references on an imported MediaPackageV2 channel and extra runtime validation on manifest naming.
Docs: https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-properties-medialive-channel-mediapackageoutputdestinationsettings.html
(MediaPackageRegionName)

Description of changes

Overview of change:

1. Add region attribute on mediapackagev2 resources
2. add "from***Arn()" functions for imports
3. Added validation to unique manifest names

Describe any new or updated permissions being added

N/A

Description of how you validated changes

Added new unit tests

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]

(This review is outdated)

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

[github-actions]

⚠️ Experimental Feature: This security report is currently in experimental phase. Results may include false positives and the rules are being actively refined.
This security report is NOT a review blocker. Please try merge from main to avoid findings unrelated to the PR.

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	Tests	Passed ✅	Skipped	Failed
Security Guardian Results	48 ran	48 passed

Test	Result
No test annotations available

• View Security Guardian Results

[github-actions]

⚠️ Experimental Feature: This security report is currently in experimental phase. Results may include false positives and the rules are being actively refined.
This security report is NOT a review blocker. Please try merge from main to avoid findings unrelated to the PR.

---

	Tests	Passed ✅	Skipped	Failed
Security Guardian Results with resolved templates	48 ran	48 passed

Test	Result
No test annotations available

• View Security Guardian Results with resolved templates