qt: Add addressList field to SendCoinsRecipient for multiple addresses

[VolodymyrBg]

This pull request adds a new field addressList to the SendCoinsRecipient class
to properly handle multiple addresses from unauthenticated payment requests.
Previously, the address field was being abused for this purpose, as noted
in a TODO comment.

The changes include:

• Adding a new addressList field to SendCoinsRecipient
• Updating the serialization methods to handle the new field
• Modifying PaymentServer to populate the new field when multiple addresses
  are present
• Updating ReceiveRequestDialog to display and copy the address list when
  available
• Adding support for the "addresses" parameter in Bitcoin URI parsing
  This provides a cleaner solution for handling multiple addresses in payment
  requests without abusing the single address field.

[DrahtBot]

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[DrahtBot]

🚧 At least one of the CI tasks failed.
_{Debug: https://github.com/bitcoin-core/gui/runs/38586514593}

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