Allow DNATed traffic in the input chain

[weiiwang01]

What this PR does

Allow DNATed traffic in the input chain.

Why we need it

Fix: #86

Checklist

• I followed the contributing guide
• I added or updated the documentation (if applicable)
• I updated docs/changelog.md with user-relevant changes
• I used AI to assist with preparing this PR
• I added or updated tests as needed (unit and integration)
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• If this is Terraform: terraform fmt passes and tflint reports no errors
• If this is Rockcraft: I updated the version