fix(client): race- and timeout-free -bblock

[michaelfig]

Description

The old -bblock relied on CometBFT's /tx_broadcast_commit endpoint, with its arbitrary, implicit 30 second timeout for block inclusion. This PR reimplements the tx -bblock flag with a subscribe(txhash)-broadcast(sync)-wait(txhash-inclusion), with no timeout.

It would be interesting to make this more robust, and offer the mechanism as a new CLI command (agd query wait-for ... ?), as well as a flag (--wait-for=<condition> ?) added to all agd tx ... and agd query tx ....

The idea would be to give power to calling scripts using the default -bsync to obtain the txHash, then code their own timeouts and/or retry loops.

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[michaelfig]

@JeancarloBarrios do you know of some prior art in Cosmos-SDK to provide similar functionality?