Subprotocol-only assets

[v16s]

Protorunes should provide a facility for its own concept of "etching" which the MessageContext may provide a handle for. This functionality should permit the genesis of a runes compatible asset which must have a RuneId in the same u128 pair structure as a runes native asset, but the entire space of bytes is permitted as long as it uses at least 1 bit of that space outside of what the runes protocol makes possible, thereby deterministically ensuring that there can not exist a clash with some asset on the runes protocol capable of entering the subprotocol via protoburn.

Upon genesis, the rune becomes an IncomingRune where the runtime balance is the max u128. It may be useful to have an additional function to credit the runtime an arbitrary amount if for any reason this byte space is not sufficient in some subprotocol architecture.

After genesis, this protorune can be used within the system anywhere and can be accessed with Edicts and handled by a protomessage as usual.