crossChainAccount derivation improvements for /txs/account

[enobayram]

This PR improves the derivation of the crossChainAccount (and crossChainId) information for cross-chain transfers served by the /txs/account endpoint.:

• For the send side, it removes the parity check comparing the amount fields of the TRANSFER and the TRANSFER_XCHAIN events. The check is redundant and it's fragile due to the volatility of decimal representations.
• For the receive side, it switches to using the X_RESUME event on the receiving transaction as the data source, instead of the TRANSFER_XCHAIN event on the sending transaction. This has 2 benefits: It allows us to remove the amount check due to the same reasons, and it avoids relying on the data from an independent block being present.

Special thanks to @Takadenoshi for identifying this issue, helping me analyze it and suggesting the fix involving the X_RESUME event!

[enobayram]

Given that CWDURL points at a chainweb-data instance listening to testnet:

Outgoing xchain transfer:

$ curl -s  "$CWDURL/txs/account/k:d63cee9e2069173f2bdd23f4739fd6f184b53b016e65fdf363f8faa569d3792f?maxheight=3980404&limit=1&offset=1" | jq -C
[
  {
    "amount": "50.0",
    "blockHash": "YAK6e67qIyCaq5oOa2RTvTw4AfUCOBNuV7OofJ0HZtI",
    "blockTime": "2024-01-24T14:29:41.078169Z",
    "chain": 4,
    "crossChainAccount": "k:58aa1853a0c1e53997c076ff9f274423f9f7548a1c22ea3210af3afeadc557e3",
    "crossChainId": 5,
    "fromAccount": "k:d63cee9e2069173f2bdd23f4739fd6f184b53b016e65fdf363f8faa569d3792f",
    "height": 3980404,
    "idx": 2,
    "requestKey": "g4bfNTgrrFf60eW0RfV7i5ix2SXGKsA-5Q7QxgoWFlM",
    "toAccount": "",
    "token": "coin"
  }
]

Incoming xchain transfer:

$ curl -s  "$CWDURL/txs/account/k:58aa1853a0c1e53997c076ff9f274423f9f7548a1c22ea3210af3afeadc557e3?maxheight=3980414&limit=1" | jq -C
[
  {
    "amount": "50.0",
    "blockHash": "B958BmmyXf3qOcpYKKDVtr5ris5mPsNSXb6JWQNEZvA",
    "blockTime": "2024-01-24T14:34:33.986913Z",
    "chain": 5,
    "crossChainAccount": "k:d63cee9e2069173f2bdd23f4739fd6f184b53b016e65fdf363f8faa569d3792f",
    "crossChainId": 4,
    "fromAccount": "",
    "height": 3980414,
    "idx": 1,
    "requestKey": "SAkgHdUXWCwDnuT9MYFbwyBKvqXXCUf-_-A0IIM1nvs",
    "toAccount": "k:58aa1853a0c1e53997c076ff9f274423f9f7548a1c22ea3210af3afeadc557e3",
    "token": "coin"
  }
]