Update referendum generation for the post-AHM world
After the Asset Hub migration, governance will take place on Asset Hub rather than the RC, which means encodings will change etc.
This also means that the XCM calls generated by opengov-cli will be incorrect for upgrades, as the assumption is that the XCM is sent from the RC.
This will happen on Kusama in mid May 2025 and Polkadot in 2025Q3. Due to the time difference, it makes sense to have this as being configurable by passing a flag or otherwise. Short term the default should be that calls and referenda are generated in the same way, then we can switch the default for Kusama then Polkadot when upgrades hit the chain in question and the migration happens.
I'm currently working on this issue