Indicate What Must Be Done to Enable Actions

https://github.com/search?q=repo%3Ahyperledger%2Ffirefly%20MsgActionNotSupported&type=code

whenever a certain action is not supported, whether its because multi-party is not enabled or because a specific plugin is not enabled on the namespace, the above error is returned.

While it makes it clear the action cannot be performed, it does not elucidate as to why it cannot be performed. This can make for a wanting error experience, where the user needs to squint at their namespace config, maybe read FF source, and guess what they need to enable or add for the action to be allowed.

We should update this error (or make separate errors) to have a formatable section to provide what specifically prevents the action from being allowed, and if something could be done to fix that.