Validate utxo_value parameters

[caydyan]

Supersedes #3383 with the same fix rebased onto the current develop branch.

move.compose() and attach.compose() accepted utxo_value values outside Bitcoin's valid output amount range. The parameter is converted to int and then used as a destination output amount, so negative or above-21M-BTC values can flow into transaction output construction.

This PR rejects invalid utxo_value values before they are returned as compose destinations.

Changes:

• Rejects negative utxo_value in move.compose().
• Rejects above-21M-BTC utxo_value in move.compose().
• Rejects negative utxo_value in attach.compose().
• Rejects above-21M-BTC utxo_value in attach.compose().
• Adds regression coverage for both message types.

Tests:

• python -m pytest counterpartycore/test/units/messages/move_test.py::test_compose counterpartycore/test/units/messages/attach_test.py::test_compose -q
• python -m pytest counterpartycore/test/units/messages/move_test.py counterpartycore/test/units/messages/attach_test.py -q
• python -m ruff check counterpartycore/lib/messages/move.py counterpartycore/lib/messages/attach.py counterpartycore/test/units/messages/move_test.py counterpartycore/test/units/messages/attach_test.py
• python -m ruff format --check counterpartycore/lib/messages/move.py counterpartycore/lib/messages/attach.py counterpartycore/test/units/messages/move_test.py counterpartycore/test/units/messages/attach_test.py
• git diff --check

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