docs: expand agent multichain safety guidance

[grayfoxd]

No description provided.

[gummy789j]

There is a section more clearly to explain the same thing

retry describes the error, not the command. timeout and rpc_error are same because
for most calls that is correct — the node never acted, so resending is free. But a command that
may have already broadcast a transaction (tx send and anything else on the submit path) can hit
timeout or rpc_error after the node accepted the transaction and before the response made it
back. In that case the outcome is unknown, not failed, and resending does not retry the original
request — it builds and signs a new transaction, which on TRON is a second, distinct transfer.
retry: "same" is correct for a timeout/rpc_error that happens while resolving a network id or
reading a balance; it is not a license to resend a broadcast blind. Reconcile with
[tx status](https://github.com/tronprotocol/wallet-cli/pull/997/changes#script-safety-never-mistake-submitted-for-confirmed) before deciding whether to
retry, exactly as the four-state model below requires.