fix(aztec-nr)!: bind owner address into owned state var nullifiers

[nchamo]

Problem

The PrivateMutable and PrivateImmutable initialization nullifiers and the SingleUseClaim claim nullifier were derived only from the storage slot and a secret derived from the owner's keys. Two accounts with the same keys but different addresses (possible since an address does not depend solely on the keys) therefore shared these nullifiers, while not sharing notes. Initializing or claiming for one account blocked the other from doing the same, and is_initialized / has_claimed for one account reported the other account's state.

Fix

The owner's address is now part of the nullifier preimage in all three state variables, keeping the state of such accounts independent. Unit tests assert that each nullifier computation differs per owner for a fixed secret. The full two-account scenario is no longer constructible in TXE since #24845 makes the key store reject accounts sharing privacy keys, which is why the coverage lives at the nullifier-computation level. A migration note documents the change.

The canonical HandshakeRegistry is also re-pinned with the fix, since it stores per-account PrivateMutable state: only its artifact changes in the pin, so the other standard contracts keep their addresses (their bytecode does not embed the registry address after #24844). The registry moves to a new address, and handshakes established with the previous instance must be re-established.

Fixes #24821

[nchamo]

Closing, in favor of #24892