Add Nu6.1 support - mainnet

Add support for NU6.1 version on ZCash

Develop MR reference: !643 (merged)

Summary by CodeRabbit

• Bug Fixes

  • Enhanced signature verification with fail-safe handling for UTXO signing to prevent retry loops.
  • Fixed batch signature-to-message pairing to use content-based matching instead of index-based ordering.
  • Improved error handling for TSS signature verification failures.

• New Features

  • Added transparent script API for Zcash address handling.

• Tests

  • Expanded test coverage for temporal storage, batch ordering, and pending transaction lifecycle scenarios.

• Chores

  • Updated Zcash dependencies to latest revision.
  • Bumped version to 1.126.2.

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