fix: json decorations for Pair[...] data members & CommunityPoolBalanceDestAddr

[pbukva]

Proposed Changes

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Linked Issues

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Types of changes

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• Bug fix (non-breaking change that fixes an issue).
• New feature added (non-breaking change that adds functionality).
• Breaking change (fix or feature that would cause existing functionality to stop working as expected).
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Further comments

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[MissingNO57]

LGTM