Add textual hex support for `uplc` utility

[SeungheonOh]

Describe the feature you'd like

Currently, parsing UPLC .flat file using uplc utility expects given file to be encoded as raw binary containing flat encoded UPLC term. Yet, it is more common to have some script source code in textual hex string format as that is how it is often used in various offchain frameworks and cardano-cli.

It would be very helpful for uplc utility to support these textual hex files as well as ones that is wrapped inside of CBOR.

Describe alternatives you've considered

No response

[Unisay]

Looks like you're describing the (yet) non-existing function readCodeEnvelope in the module PlutusLedgerApi.Envelope
https://github.com/IntersectMBO/plutus/pull/7197/files

[kwxm]

Note that there's also a plutus executable that was supposed to be a unified tool that would replace all of plc, pir, and uplc . We never really completed the move though: perhaps we should think about that again some time.