prefer transaction id over txid

[zancas]

No description provided.

[fluidvanadium]

in this case, i disagree because TxId is the LRZ type we rely on.

[zancas]

I see your point, but couldn't that actually be an argument in favor? The developer can read the foreign crate type in the signature.. now.. without further action it's disambiguated by the ident as "a transaction" as opposed to e.g. "a transmission". So our more-explicit naming convention produces an ident that helps to (locally) fix an ambiguity introduced by the slightly less careful name being used elsewhere?