Refactor IBC event handling to make use of TypedEvents

[hdevalence]

Is your feature request related to a problem? Please describe.

One of the issues we ran into while debugging compatibility between pd and rly was inconsistent encoding of event data that was intended to be picked up by the relayer. Currently, we handle events with events::named_event(...) -> Event constructors that take typed values and create events from them. However, this is still somewhat error-prone.

Describe the solution you'd like

After informalsystems/tendermint-rs#1288 lands upstream, we can define our own domain types representing the data in abci::Events. This will give us a more maintainable, single source of truth on how our event serialization should be defined.

[plaidfinch]

Instead of changing the types in our penumbra-ibc crate, we should try to align with the ibc-types refactoring. In other words, this should be part of the ibc-types refactoring.

[plaidfinch]

Blocked on IBC types refactoring.

[conorsch]

ibc-types refactoring is complete. Unclear to me whether this is related to #2385.

[conorsch]

Resolved in #2829