feat: add overflow validation for input and recipient sums in state transitions

[shumkov]

Issue being fixed or feature implemented

Some overflow checks are missing. It won't happen due to other logic, but it's better to have it anyway.

What was done?

• Added additional overflow checks.

How Has This Been Tested?

Add unit tests

Breaking Changes

None

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have added "!" to the title and described breaking changes in the corresponding section if my code contains any
• I have made corresponding changes to the documentation if needed

For repository code-owners and collaborators only

• I have assigned this pull request to a milestone

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✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch fix/overflows

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[QuantumExplorer]

These issues can't actually happen, but I guess we should merge this in, it doesn't really add more processing and it hardens the system.