fix: use latest block for eth_fillTransaction gas estimation

CHANGELOG.md

@@ -54,6 +54,7 @@
 - [\#993](https://github.com/cosmos/evm/pull/993) Enforce `src_callback` contract address to match the packet sender for IBC acknowledgement and timeout callbacks to prevent arbitrary contract execution.
 - [\#1050](https://github.com/cosmos/evm/pull/1050) Align precompile gas calculation with expected EVM gas semantics.
 - [\#1107](https://github.com/cosmos/evm/pull/1107) Skip StateDB commit error transactions during receipt conversion to prevent `invalid message index` errors in block RPCs.
+- [\#1138](https://github.com/cosmos/evm/pull/1138) Use the latest block instead of numeric `0` when `eth_fillTransaction` estimates gas so the RPC does not resolve block 1 by mistake.
 
 
 ## v0.6.0

rpc/backend/call_tx.go

@@ -279,7 +279,7 @@ func (b *Backend) SetTxDefaults(ctx context.Context, args evmtypes.TransactionAr
 			Nonce:                args.Nonce,
 		}
 
-		blockNr := rpctypes.NewBlockNumber(big.NewInt(0))
+		blockNr := rpctypes.EthLatestBlockNumber
 		blockNrOrHash := rpctypes.BlockNumberOrHash{BlockNumber: &blockNr}
 		estimated, err := b.EstimateGas(ctx, callArgs, &blockNrOrHash, nil)
 		if err != nil {