Returns CDAO lifecycle status plus Avalanche network status for a broadcast transaction, looked up by txHash
(the Avalanche transaction ID returned by /submit). The optional chain query parameter helps CDAO route the
lookup for C-Chain atomic exports (C) versus P-Chain transactions (P).

The response is intended for frontend polling, custodian reconciliation, and operational support. It includes the
CDAO operation and intent status, network status, transaction hash when available, chain/VM routing metadata,
failure reason if any, and the latest update timestamp.

Status interpretation depends on the chain. SUBMITTED means the RPC accepted the broadcast. Final success is
ACCEPTED for C-Chain atomic export transactions and COMMITTED for P-Chain stake, delegate, and import
transactions.