feat: add unsigned sweep logic for vet

[at31416]

This pull request enhances the VeChain (VET) recovery functionality by adding support for unsigned sweep recoveries using TSS (Threshold Signature Scheme). It introduces new parameters and logic to handle unsigned sweeps, updates the recovery mocks and tests accordingly, and refines the type definitions to support these changes.

VET Recovery Enhancements:

• Added support for unsigned sweep recoveries by allowing bitgoKey as an alternative to userKey/backupKey in the RecoverOptions type, and implemented the corresponding logic in the Vet coin class to derive the public key and construct the unsigned transaction. [1] [2] [3]
• Updated the VET recovery mocks in nockVetRecovery to accept a dynamic baseAddress parameter, enabling more flexible and reusable test setups. [1] [2] [3]

Testing Improvements:

• Un-commented and refactored the test for constructing an unsigned sweep transaction with TSS, now using the updated mock and recovery logic, ensuring unsigned sweep recoveries are properly tested.
• Updated the existing test for MPCv2 TSS recovery to use the new baseAddress parameter in the recovery mocks, improving test accuracy and maintainability.

Dependency and Import Updates:

• Added import of @bitgo/sdk-lib-mpc in the VET coin implementation to support public key derivation for unsigned sweeps.

Ticket: COIN-6042