feat: add flexible nullifier to update circuit

[ananas-block]

Motivation:

• the batch update circuit assumes nullifying by replacing compressed_account_hash with [0u8;32]
• we want to nullify with nullifier= H(compressed_account_hash, tx_hash) so that we can access the transaction that spent a compressed account in a proof
  -tx_hash = HashChain([..tx_input_hashes,... tx_output_hashes])

Changes:

• leaves_hashchain is hashchain of nullifiers
• it is not necessary to check nullifier derivation since we derive nullifiers onchain
• update leaf with nullifier instead of empty_leaf

TODO:

• generate new proving keys and upload those